one collector per agg request instead per bucket (#2759)

* improve bench

* add more tests for new collection type

* one collector per agg request instead per bucket

In this refactoring a collector knows in which bucket of the parent
their data is in. This allows to convert the previous approach of one
collector per bucket to one collector per request.

low card bucket optimization

* reduce dynamic dispatch, faster term agg

* use radix map, fix prepare_max_bucket

use paged term map in term agg
use special no sub agg term map impl

* specialize columntype in stats

* remove stacktrace bloat, use &mut helper

increase cache to 2048

* cleanup

remove clone
move data in term req, single doc opt for stats

* add comment

* share column block accessor

* simplify fetch block in column_block_accessor

* split subaggcache into two trait impls

* move partitions to heap

* fix name, add comment

---------

Co-authored-by: Pascal Seitz <pascal.seitz@gmail.com>

.github/workflows/test.yml

@@ -39,11 +39,11 @@ jobs:
 
     - name: Check Formatting
       run: cargo +nightly fmt --all -- --check
-    
+
     - name: Check Stable Compilation
       run: cargo build --all-features
 
-    
+
     - name: Check Bench Compilation
       run: cargo +nightly bench --no-run --profile=dev --all-features
 
@@ -59,10 +59,10 @@ jobs:
 
     strategy:
       matrix:
-        features: [
+        features:
-            { label: "all", flags: "mmap,stopwords,lz4-compression,zstd-compression,failpoints" },
+          - { label: "all", flags: "mmap,stopwords,lz4-compression,zstd-compression,failpoints,stemmer" }
-            { label: "quickwit", flags: "mmap,quickwit,failpoints" }
+          - { label: "quickwit", flags: "mmap,quickwit,failpoints" }
-        ]
+          - { label: "none", flags: "" }
 
     name: test-${{ matrix.features.label}}
 
@@ -80,7 +80,21 @@ jobs:
     - uses: Swatinem/rust-cache@v2
 
     - name: Run tests
-      run: cargo +stable nextest run --features ${{ matrix.features.flags }} --verbose --workspace
+      run: |
+        # if matrix.feature.flags is empty then run on --lib to avoid compiling examples
+        # (as most of them rely on mmap) otherwise run all
+        if [ -z "${{ matrix.features.flags }}" ]; then
+          cargo +stable nextest run --lib --no-default-features --verbose --workspace
+        else
+          cargo +stable nextest run --features ${{ matrix.features.flags }} --no-default-features --verbose --workspace
+        fi
 
     - name: Run doctests
-      run: cargo +stable test --doc --features ${{ matrix.features.flags }} --verbose --workspace
+      run: |
+        # if matrix.feature.flags is empty then run on --lib to avoid compiling examples
+        # (as most of them rely on mmap) otherwise run all
+        if [ -z "${{ matrix.features.flags }}" ]; then
+          echo "no doctest for no feature flag"
+        else
+          cargo +stable test --doc --features ${{ matrix.features.flags }} --verbose --workspace
+        fi

Cargo.toml

@@ -37,7 +37,7 @@ fs4 = { version = "0.13.1", optional = true }
 levenshtein_automata = "0.2.1"
 uuid = { version = "1.0.0", features = ["v4", "serde"] }
 crossbeam-channel = "0.5.4"
-rust-stemmers = "1.2.0"
+rust-stemmers = { version = "1.2.0", optional = true }
 downcast-rs = "2.0.1"
 bitpacking = { version = "0.9.2", default-features = false, features = [
     "bitpacker4x",
@@ -113,7 +113,8 @@ debug-assertions = true
 overflow-checks = true
 
 [features]
-default = ["mmap", "stopwords", "lz4-compression", "columnar-zstd-compression"]
+default = ["mmap", "stopwords", "lz4-compression", "columnar-zstd-compression", "stemmer"]
+stemmer = ["rust-stemmers"]
 mmap = ["fs4", "tempfile", "memmap2"]
 stopwords = []
 

benches/agg_bench.rs

@@ -54,33 +54,33 @@ fn bench_agg(mut group: InputGroup<Index>) {
     register!(group, stats_f64);
     register!(group, extendedstats_f64);
     register!(group, percentiles_f64);
-    register!(group, terms_few);
+    register!(group, terms_7);
     register!(group, terms_all_unique);
-    register!(group, terms_many);
+    register!(group, terms_150_000);
     register!(group, terms_many_top_1000);
     register!(group, terms_many_order_by_term);
     register!(group, terms_many_with_top_hits);
     register!(group, terms_all_unique_with_avg_sub_agg);
     register!(group, terms_many_with_avg_sub_agg);
-    register!(group, terms_few_with_avg_sub_agg);
     register!(group, terms_status_with_avg_sub_agg);
-    register!(group, terms_status);
-    register!(group, terms_few_with_histogram);
     register!(group, terms_status_with_histogram);
+    register!(group, terms_zipf_1000);
+    register!(group, terms_zipf_1000_with_histogram);
+    register!(group, terms_zipf_1000_with_avg_sub_agg);
 
     register!(group, terms_many_json_mixed_type_with_avg_sub_agg);
 
     register!(group, cardinality_agg);
-    register!(group, terms_few_with_cardinality_agg);
+    register!(group, terms_status_with_cardinality_agg);
 
     register!(group, range_agg);
     register!(group, range_agg_with_avg_sub_agg);
-    register!(group, range_agg_with_term_agg_few);
+    register!(group, range_agg_with_term_agg_status);
     register!(group, range_agg_with_term_agg_many);
     register!(group, histogram);
     register!(group, histogram_hard_bounds);
     register!(group, histogram_with_avg_sub_agg);
-    register!(group, histogram_with_term_agg_few);
+    register!(group, histogram_with_term_agg_status);
     register!(group, avg_and_range_with_avg_sub_agg);
 
     // Filter aggregation benchmarks
@@ -159,10 +159,10 @@ fn cardinality_agg(index: &Index) {
     });
     execute_agg(index, agg_req);
 }
-fn terms_few_with_cardinality_agg(index: &Index) {
+fn terms_status_with_cardinality_agg(index: &Index) {
     let agg_req = json!({
         "my_texts": {
-            "terms": { "field": "text_few_terms" },
+            "terms": { "field": "text_few_terms_status" },
             "aggs": {
                 "cardinality": {
                     "cardinality": {
@@ -175,13 +175,7 @@ fn terms_few_with_cardinality_agg(index: &Index) {
     execute_agg(index, agg_req);
 }
 
-fn terms_few(index: &Index) {
+fn terms_7(index: &Index) {
-    let agg_req = json!({
-        "my_texts": { "terms": { "field": "text_few_terms" } },
-    });
-    execute_agg(index, agg_req);
-}
-fn terms_status(index: &Index) {
     let agg_req = json!({
         "my_texts": { "terms": { "field": "text_few_terms_status" } },
     });
@@ -194,7 +188,7 @@ fn terms_all_unique(index: &Index) {
     execute_agg(index, agg_req);
 }
 
-fn terms_many(index: &Index) {
+fn terms_150_000(index: &Index) {
     let agg_req = json!({
         "my_texts": { "terms": { "field": "text_many_terms" } },
     });
@@ -253,17 +247,6 @@ fn terms_all_unique_with_avg_sub_agg(index: &Index) {
     });
     execute_agg(index, agg_req);
 }
-fn terms_few_with_histogram(index: &Index) {
-    let agg_req = json!({
-        "my_texts": {
-            "terms": { "field": "text_few_terms" },
-            "aggs": {
-                "histo": {"histogram": { "field": "score_f64", "interval": 10 }}
-            }
-        }
-    });
-    execute_agg(index, agg_req);
-}
 fn terms_status_with_histogram(index: &Index) {
     let agg_req = json!({
         "my_texts": {
@@ -276,17 +259,18 @@ fn terms_status_with_histogram(index: &Index) {
     execute_agg(index, agg_req);
 }
 
-fn terms_few_with_avg_sub_agg(index: &Index) {
+fn terms_zipf_1000_with_histogram(index: &Index) {
     let agg_req = json!({
         "my_texts": {
-            "terms": { "field": "text_few_terms" },
+            "terms": { "field": "text_1000_terms_zipf" },
             "aggs": {
-                "average_f64": { "avg": { "field": "score_f64" } }
+                "histo": {"histogram": { "field": "score_f64", "interval": 10 }}
             }
-        },
+        }
     });
     execute_agg(index, agg_req);
 }
+
 fn terms_status_with_avg_sub_agg(index: &Index) {
     let agg_req = json!({
         "my_texts": {
@@ -299,6 +283,25 @@ fn terms_status_with_avg_sub_agg(index: &Index) {
     execute_agg(index, agg_req);
 }
 
+fn terms_zipf_1000_with_avg_sub_agg(index: &Index) {
+    let agg_req = json!({
+        "my_texts": {
+            "terms": { "field": "text_1000_terms_zipf" },
+            "aggs": {
+                "average_f64": { "avg": { "field": "score_f64" } }
+            }
+        },
+    });
+    execute_agg(index, agg_req);
+}
+
+fn terms_zipf_1000(index: &Index) {
+    let agg_req = json!({
+        "my_texts": { "terms": { "field": "text_1000_terms_zipf" } },
+    });
+    execute_agg(index, agg_req);
+}
+
 fn terms_many_json_mixed_type_with_avg_sub_agg(index: &Index) {
     let agg_req = json!({
         "my_texts": {
@@ -354,7 +357,7 @@ fn range_agg_with_avg_sub_agg(index: &Index) {
     execute_agg(index, agg_req);
 }
 
-fn range_agg_with_term_agg_few(index: &Index) {
+fn range_agg_with_term_agg_status(index: &Index) {
     let agg_req = json!({
         "rangef64": {
             "range": {
@@ -369,7 +372,7 @@ fn range_agg_with_term_agg_few(index: &Index) {
                 ]
             },
             "aggs": {
-                "my_texts": { "terms": { "field": "text_few_terms" } },
+                "my_texts": { "terms": { "field": "text_few_terms_status" } },
             }
         },
     });
@@ -425,12 +428,12 @@ fn histogram_with_avg_sub_agg(index: &Index) {
     });
     execute_agg(index, agg_req);
 }
-fn histogram_with_term_agg_few(index: &Index) {
+fn histogram_with_term_agg_status(index: &Index) {
     let agg_req = json!({
         "rangef64": {
             "histogram": { "field": "score_f64", "interval": 10 },
             "aggs": {
-                "my_texts": { "terms": { "field": "text_few_terms" } }
+                "my_texts": { "terms": { "field": "text_few_terms_status" } }
             }
         }
     });
@@ -475,6 +478,13 @@ fn get_collector(agg_req: Aggregations) -> AggregationCollector {
 }
 
 fn get_test_index_bench(cardinality: Cardinality) -> tantivy::Result<Index> {
+    // Flag to use existing index
+    let reuse_index = std::env::var("REUSE_AGG_BENCH_INDEX").is_ok();
+    if reuse_index && std::path::Path::new("agg_bench").exists() {
+        return Index::open_in_dir("agg_bench");
+    }
+    // crreate dir
+    std::fs::create_dir_all("agg_bench")?;
     let mut schema_builder = Schema::builder();
     let text_fieldtype = tantivy::schema::TextOptions::default()
         .set_indexing_options(
@@ -486,24 +496,44 @@ fn get_test_index_bench(cardinality: Cardinality) -> tantivy::Result<Index> {
     let text_field_all_unique_terms =
         schema_builder.add_text_field("text_all_unique_terms", STRING | FAST);
     let text_field_many_terms = schema_builder.add_text_field("text_many_terms", STRING | FAST);
-    let text_field_many_terms = schema_builder.add_text_field("text_many_terms", STRING | FAST);
-    let text_field_few_terms = schema_builder.add_text_field("text_few_terms", STRING | FAST);
     let text_field_few_terms_status =
         schema_builder.add_text_field("text_few_terms_status", STRING | FAST);
+    let text_field_1000_terms_zipf =
+        schema_builder.add_text_field("text_1000_terms_zipf", STRING | FAST);
     let score_fieldtype = tantivy::schema::NumericOptions::default().set_fast();
     let score_field = schema_builder.add_u64_field("score", score_fieldtype.clone());
     let score_field_f64 = schema_builder.add_f64_field("score_f64", score_fieldtype.clone());
     let score_field_i64 = schema_builder.add_i64_field("score_i64", score_fieldtype);
-    let index = Index::create_from_tempdir(schema_builder.build())?;
+    // use tmp dir
-    let few_terms_data = ["INFO", "ERROR", "WARN", "DEBUG"];
+    let index = if reuse_index {
-    // Approximate production log proportions: INFO dominant, WARN and DEBUG occasional, ERROR rare.
+        Index::create_in_dir("agg_bench", schema_builder.build())?
-    let log_level_distribution = WeightedIndex::new([80u32, 3, 12, 5]).unwrap();
+    } else {
+        Index::create_from_tempdir(schema_builder.build())?
+    };
+    // Approximate log proportions
+    let status_field_data = [
+        ("INFO", 8000),
+        ("ERROR", 300),
+        ("WARN", 1200),
+        ("DEBUG", 500),
+        ("OK", 500),
+        ("CRITICAL", 20),
+        ("EMERGENCY", 1),
+    ];
+    let log_level_distribution =
+        WeightedIndex::new(status_field_data.iter().map(|item| item.1)).unwrap();
 
     let lg_norm = rand_distr::LogNormal::new(2.996f64, 0.979f64).unwrap();
 
     let many_terms_data = (0..150_000)
         .map(|num| format!("author{num}"))
         .collect::<Vec<_>>();
+
+    // Prepare 1000 unique terms sampled using a Zipf distribution.
+    // Exponent ~1.1 approximates top-20 terms covering around ~20%.
+    let terms_1000: Vec<String> = (1..=1000).map(|i| format!("term_{i}")).collect();
+    let zipf_1000 = rand_distr::Zipf::new(1000, 1.1f64).unwrap();
+
     {
         let mut rng = StdRng::from_seed([1u8; 32]);
         let mut index_writer = index.writer_with_num_threads(1, 200_000_000)?;
@@ -513,8 +543,12 @@ fn get_test_index_bench(cardinality: Cardinality) -> tantivy::Result<Index> {
             index_writer.add_document(doc!())?;
         }
         if cardinality == Cardinality::Multivalued {
-            let log_level_sample_a = few_terms_data[log_level_distribution.sample(&mut rng)];
+            let log_level_sample_a = status_field_data[log_level_distribution.sample(&mut rng)].0;
-            let log_level_sample_b = few_terms_data[log_level_distribution.sample(&mut rng)];
+            let log_level_sample_b = status_field_data[log_level_distribution.sample(&mut rng)].0;
+            let idx_a = zipf_1000.sample(&mut rng) as usize - 1;
+            let idx_b = zipf_1000.sample(&mut rng) as usize - 1;
+            let term_1000_a = &terms_1000[idx_a];
+            let term_1000_b = &terms_1000[idx_b];
             index_writer.add_document(doc!(
                 json_field => json!({"mixed_type": 10.0}),
                 json_field => json!({"mixed_type": 10.0}),
@@ -524,10 +558,10 @@ fn get_test_index_bench(cardinality: Cardinality) -> tantivy::Result<Index> {
                 text_field_all_unique_terms => "coolo",
                 text_field_many_terms => "cool",
                 text_field_many_terms => "cool",
-                text_field_few_terms => "cool",
-                text_field_few_terms => "cool",
                 text_field_few_terms_status => log_level_sample_a,
                 text_field_few_terms_status => log_level_sample_b,
+                text_field_1000_terms_zipf => term_1000_a.as_str(),
+                text_field_1000_terms_zipf => term_1000_b.as_str(),
                 score_field => 1u64,
                 score_field => 1u64,
                 score_field_f64 => lg_norm.sample(&mut rng),
@@ -554,8 +588,8 @@ fn get_test_index_bench(cardinality: Cardinality) -> tantivy::Result<Index> {
                 json_field => json,
                 text_field_all_unique_terms => format!("unique_term_{}", rng.gen::<u64>()),
                 text_field_many_terms => many_terms_data.choose(&mut rng).unwrap().to_string(),
-                text_field_few_terms => few_terms_data.choose(&mut rng).unwrap().to_string(),
+                text_field_few_terms_status => status_field_data[log_level_distribution.sample(&mut rng)].0,
-                text_field_few_terms_status => few_terms_data[log_level_distribution.sample(&mut rng)],
+                text_field_1000_terms_zipf => terms_1000[zipf_1000.sample(&mut rng) as usize - 1].as_str(),
                 score_field => val as u64,
                 score_field_f64 => lg_norm.sample(&mut rng),
                 score_field_i64 => val as i64,
@@ -607,7 +641,7 @@ fn filter_agg_all_query_with_sub_aggs(index: &Index) {
                 "avg_score": { "avg": { "field": "score" } },
                 "stats_score": { "stats": { "field": "score_f64" } },
                 "terms_text": {
-                    "terms": { "field": "text_few_terms" }
+                    "terms": { "field": "text_few_terms_status" }
                 }
             }
         }
@@ -623,7 +657,7 @@ fn filter_agg_term_query_with_sub_aggs(index: &Index) {
                 "avg_score": { "avg": { "field": "score" } },
                 "stats_score": { "stats": { "field": "score_f64" } },
                 "terms_text": {
-                    "terms": { "field": "text_few_terms" }
+                    "terms": { "field": "text_few_terms_status" }
                 }
             }
         }

columnar/src/block_accessor.rs

@@ -29,12 +29,20 @@ impl<T: PartialOrd + Copy + std::fmt::Debug + Send + Sync + 'static + Default>
         }
     }
     #[inline]
-    pub fn fetch_block_with_missing(&mut self, docs: &[u32], accessor: &Column<T>, missing: T) {
+    pub fn fetch_block_with_missing(
+        &mut self,
+        docs: &[u32],
+        accessor: &Column<T>,
+        missing: Option<T>,
+    ) {
         self.fetch_block(docs, accessor);
         // no missing values
         if accessor.index.get_cardinality().is_full() {
             return;
         }
+        let Some(missing) = missing else {
+            return;
+        };
 
         // We can compare docid_cache length with docs to find missing docs
         // For multi value columns we can't rely on the length and always need to scan

columnar/src/column/mod.rs

@@ -85,8 +85,8 @@ impl<T: PartialOrd + Copy + Debug + Send + Sync + 'static> Column<T> {
     }
 
     #[inline]
-    pub fn first(&self, row_id: RowId) -> Option<T> {
+    pub fn first(&self, doc_id: DocId) -> Option<T> {
-        self.values_for_doc(row_id).next()
+        self.values_for_doc(doc_id).next()
     }
 
     /// Load the first value for each docid in the provided slice.

columnar/src/tests.rs

@@ -60,7 +60,7 @@ fn test_dataframe_writer_bool() {
     let DynamicColumn::Bool(bool_col) = dyn_bool_col else {
         panic!();
     };
-    let vals: Vec<Option<bool>> = (0..5).map(|row_id| bool_col.first(row_id)).collect();
+    let vals: Vec<Option<bool>> = (0..5).map(|doc_id| bool_col.first(doc_id)).collect();
     assert_eq!(&vals, &[None, Some(false), None, Some(true), None,]);
 }
 
@@ -108,7 +108,7 @@ fn test_dataframe_writer_ip_addr() {
     let DynamicColumn::IpAddr(ip_col) = dyn_bool_col else {
         panic!();
     };
-    let vals: Vec<Option<Ipv6Addr>> = (0..5).map(|row_id| ip_col.first(row_id)).collect();
+    let vals: Vec<Option<Ipv6Addr>> = (0..5).map(|doc_id| ip_col.first(doc_id)).collect();
     assert_eq!(
         &vals,
         &[
@@ -169,7 +169,7 @@ fn test_dictionary_encoded_str() {
     let DynamicColumn::Str(str_col) = col_handles[0].open().unwrap() else {
         panic!();
     };
-    let index: Vec<Option<u64>> = (0..5).map(|row_id| str_col.ords().first(row_id)).collect();
+    let index: Vec<Option<u64>> = (0..5).map(|doc_id| str_col.ords().first(doc_id)).collect();
     assert_eq!(index, &[None, Some(0), None, Some(2), Some(1)]);
     assert_eq!(str_col.num_rows(), 5);
     let mut term_buffer = String::new();
@@ -204,7 +204,7 @@ fn test_dictionary_encoded_bytes() {
         panic!();
     };
     let index: Vec<Option<u64>> = (0..5)
-        .map(|row_id| bytes_col.ords().first(row_id))
+        .map(|doc_id| bytes_col.ords().first(doc_id))
         .collect();
     assert_eq!(index, &[None, Some(0), None, Some(2), Some(1)]);
     assert_eq!(bytes_col.num_rows(), 5);

common/src/bitset.rs

@@ -181,6 +181,14 @@ pub struct BitSet {
     len: u64,
     max_value: u32,
 }
+impl std::fmt::Debug for BitSet {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("BitSet")
+            .field("len", &self.len)
+            .field("max_value", &self.max_value)
+            .finish()
+    }
+}
 
 fn num_buckets(max_val: u32) -> u32 {
     max_val.div_ceil(64u32)

src/aggregation/agg_data.rs

@@ -1,4 +1,4 @@
-use columnar::{Column, ColumnType, StrColumn};
+use columnar::{Column, ColumnBlockAccessor, ColumnType, StrColumn};
 use common::BitSet;
 use rustc_hash::FxHashSet;
 use serde::Serialize;
@@ -10,16 +10,16 @@ use crate::aggregation::accessor_helpers::{
 };
 use crate::aggregation::agg_req::{Aggregation, AggregationVariants, Aggregations};
 use crate::aggregation::bucket::{
-    FilterAggReqData, HistogramAggReqData, HistogramBounds, IncludeExcludeParam,
+    build_segment_filter_collector, build_segment_range_collector, FilterAggReqData,
-    MissingTermAggReqData, RangeAggReqData, SegmentFilterCollector, SegmentHistogramCollector,
+    HistogramAggReqData, HistogramBounds, IncludeExcludeParam, MissingTermAggReqData,
-    SegmentRangeCollector, TermMissingAgg, TermsAggReqData, TermsAggregation,
+    RangeAggReqData, SegmentHistogramCollector, TermMissingAgg, TermsAggReqData, TermsAggregation,
     TermsAggregationInternal,
 };
 use crate::aggregation::metric::{
-    AverageAggregation, CardinalityAggReqData, CardinalityAggregationReq, CountAggregation,
+    build_segment_stats_collector, AverageAggregation, CardinalityAggReqData,
-    ExtendedStatsAggregation, MaxAggregation, MetricAggReqData, MinAggregation,
+    CardinalityAggregationReq, CountAggregation, ExtendedStatsAggregation, MaxAggregation,
-    SegmentCardinalityCollector, SegmentExtendedStatsCollector, SegmentPercentilesCollector,
+    MetricAggReqData, MinAggregation, SegmentCardinalityCollector, SegmentExtendedStatsCollector,
-    SegmentStatsCollector, StatsAggregation, StatsType, SumAggregation, TopHitsAggReqData,
+    SegmentPercentilesCollector, StatsAggregation, StatsType, SumAggregation, TopHitsAggReqData,
     TopHitsSegmentCollector,
 };
 use crate::aggregation::segment_agg_result::{
@@ -35,6 +35,7 @@ pub struct AggregationsSegmentCtx {
     /// Request data for each aggregation type.
     pub per_request: PerRequestAggSegCtx,
     pub context: AggContextParams,
+    pub column_block_accessor: ColumnBlockAccessor<u64>,
 }
 
 impl AggregationsSegmentCtx {
@@ -107,21 +108,14 @@ impl AggregationsSegmentCtx {
             .as_deref()
             .expect("range_req_data slot is empty (taken)")
     }
-    #[inline]
-    pub(crate) fn get_filter_req_data(&self, idx: usize) -> &FilterAggReqData {
-        self.per_request.filter_req_data[idx]
-            .as_deref()
-            .expect("filter_req_data slot is empty (taken)")
-    }
 
     // ---------- mutable getters ----------
 
     #[inline]
-    pub(crate) fn get_term_req_data_mut(&mut self, idx: usize) -> &mut TermsAggReqData {
+    pub(crate) fn get_metric_req_data_mut(&mut self, idx: usize) -> &mut MetricAggReqData {
-        self.per_request.term_req_data[idx]
+        &mut self.per_request.stats_metric_req_data[idx]
-            .as_deref_mut()
-            .expect("term_req_data slot is empty (taken)")
     }
+
     #[inline]
     pub(crate) fn get_cardinality_req_data_mut(
         &mut self,
@@ -129,10 +123,7 @@ impl AggregationsSegmentCtx {
     ) -> &mut CardinalityAggReqData {
         &mut self.per_request.cardinality_req_data[idx]
     }
-    #[inline]
+
-    pub(crate) fn get_metric_req_data_mut(&mut self, idx: usize) -> &mut MetricAggReqData {
-        &mut self.per_request.stats_metric_req_data[idx]
-    }
     #[inline]
     pub(crate) fn get_histogram_req_data_mut(&mut self, idx: usize) -> &mut HistogramAggReqData {
         self.per_request.histogram_req_data[idx]
@@ -142,21 +133,6 @@ impl AggregationsSegmentCtx {
 
     // ---------- take / put (terms, histogram, range) ----------
 
-    /// Move out the boxed Terms request at `idx`, leaving `None`.
-    #[inline]
-    pub(crate) fn take_term_req_data(&mut self, idx: usize) -> Box<TermsAggReqData> {
-        self.per_request.term_req_data[idx]
-            .take()
-            .expect("term_req_data slot is empty (taken)")
-    }
-
-    /// Put back a Terms request into an empty slot at `idx`.
-    #[inline]
-    pub(crate) fn put_back_term_req_data(&mut self, idx: usize, value: Box<TermsAggReqData>) {
-        debug_assert!(self.per_request.term_req_data[idx].is_none());
-        self.per_request.term_req_data[idx] = Some(value);
-    }
-
     /// Move out the boxed Histogram request at `idx`, leaving `None`.
     #[inline]
     pub(crate) fn take_histogram_req_data(&mut self, idx: usize) -> Box<HistogramAggReqData> {
@@ -320,6 +296,7 @@ impl PerRequestAggSegCtx {
 
     /// Convert the aggregation tree into a serializable struct representation.
     /// Each node contains: { name, kind, children }.
+    #[allow(dead_code)]
     pub fn get_view_tree(&self) -> Vec<AggTreeViewNode> {
         fn node_to_view(node: &AggRefNode, pr: &PerRequestAggSegCtx) -> AggTreeViewNode {
             let mut children: Vec<AggTreeViewNode> =
@@ -345,12 +322,19 @@ impl PerRequestAggSegCtx {
 pub(crate) fn build_segment_agg_collectors_root(
     req: &mut AggregationsSegmentCtx,
 ) -> crate::Result<Box<dyn SegmentAggregationCollector>> {
-    build_segment_agg_collectors(req, &req.per_request.agg_tree.clone())
+    build_segment_agg_collectors_generic(req, &req.per_request.agg_tree.clone())
 }
 
 pub(crate) fn build_segment_agg_collectors(
     req: &mut AggregationsSegmentCtx,
     nodes: &[AggRefNode],
+) -> crate::Result<Box<dyn SegmentAggregationCollector>> {
+    build_segment_agg_collectors_generic(req, nodes)
+}
+
+fn build_segment_agg_collectors_generic(
+    req: &mut AggregationsSegmentCtx,
+    nodes: &[AggRefNode],
 ) -> crate::Result<Box<dyn SegmentAggregationCollector>> {
     let mut collectors = Vec::new();
     for node in nodes.iter() {
@@ -388,6 +372,8 @@ pub(crate) fn build_segment_agg_collector(
             Ok(Box::new(SegmentCardinalityCollector::from_req(
                 req_data.column_type,
                 node.idx_in_req_data,
+                req_data.accessor.clone(),
+                req_data.missing_value_for_accessor,
             )))
         }
         AggKind::StatsKind(stats_type) => {
@@ -398,20 +384,21 @@ pub(crate) fn build_segment_agg_collector(
                 | StatsType::Count
                 | StatsType::Max
                 | StatsType::Min
-                | StatsType::Stats => Ok(Box::new(SegmentStatsCollector::from_req(
+                | StatsType::Stats => build_segment_stats_collector(req_data),
-                    node.idx_in_req_data,
+                StatsType::ExtendedStats(sigma) => Ok(Box::new(
-                ))),
+                    SegmentExtendedStatsCollector::from_req(req_data, sigma),
-                StatsType::ExtendedStats(sigma) => {
-                    Ok(Box::new(SegmentExtendedStatsCollector::from_req(
-                        req_data.field_type,
-                        sigma,
-                        node.idx_in_req_data,
-                        req_data.missing,
-                    )))
-                }
-                StatsType::Percentiles => Ok(Box::new(
-                    SegmentPercentilesCollector::from_req_and_validate(node.idx_in_req_data)?,
                 )),
+                StatsType::Percentiles => {
+                    let req_data = req.get_metric_req_data_mut(node.idx_in_req_data);
+                    Ok(Box::new(
+                        SegmentPercentilesCollector::from_req_and_validate(
+                            req_data.field_type,
+                            req_data.missing_u64,
+                            req_data.accessor.clone(),
+                            node.idx_in_req_data,
+                        ),
+                    ))
+                }
             }
         }
         AggKind::TopHits => {
@@ -428,12 +415,8 @@ pub(crate) fn build_segment_agg_collector(
         AggKind::DateHistogram => Ok(Box::new(SegmentHistogramCollector::from_req_and_validate(
             req, node,
         )?)),
-        AggKind::Range => Ok(Box::new(SegmentRangeCollector::from_req_and_validate(
+        AggKind::Range => Ok(build_segment_range_collector(req, node)?),
-            req, node,
+        AggKind::Filter => build_segment_filter_collector(req, node),
-        )?)),
-        AggKind::Filter => Ok(Box::new(SegmentFilterCollector::from_req_and_validate(
-            req, node,
-        )?)),
     }
 }
 
@@ -493,6 +476,7 @@ pub(crate) fn build_aggregations_data_from_req(
     let mut data = AggregationsSegmentCtx {
         per_request: Default::default(),
         context,
+        column_block_accessor: ColumnBlockAccessor::default(),
     };
 
     for (name, agg) in aggs.iter() {
@@ -521,9 +505,9 @@ fn build_nodes(
             let idx_in_req_data = data.push_range_req_data(RangeAggReqData {
                 accessor,
                 field_type,
-                column_block_accessor: Default::default(),
                 name: agg_name.to_string(),
                 req: range_req.clone(),
+                is_top_level,
             });
             let children = build_children(&req.sub_aggregation, reader, segment_ordinal, data)?;
             Ok(vec![AggRefNode {
@@ -541,9 +525,7 @@ fn build_nodes(
             let idx_in_req_data = data.push_histogram_req_data(HistogramAggReqData {
                 accessor,
                 field_type,
-                column_block_accessor: Default::default(),
                 name: agg_name.to_string(),
-                sub_aggregation_blueprint: None,
                 req: histo_req.clone(),
                 is_date_histogram: false,
                 bounds: HistogramBounds {
@@ -568,9 +550,7 @@ fn build_nodes(
             let idx_in_req_data = data.push_histogram_req_data(HistogramAggReqData {
                 accessor,
                 field_type,
-                column_block_accessor: Default::default(),
                 name: agg_name.to_string(),
-                sub_aggregation_blueprint: None,
                 req: histo_req,
                 is_date_histogram: true,
                 bounds: HistogramBounds {
@@ -650,7 +630,6 @@ fn build_nodes(
             let idx_in_req_data = data.push_metric_req_data(MetricAggReqData {
                 accessor,
                 field_type,
-                column_block_accessor: Default::default(),
                 name: agg_name.to_string(),
                 collecting_for,
                 missing: *missing,
@@ -678,7 +657,6 @@ fn build_nodes(
             let idx_in_req_data = data.push_metric_req_data(MetricAggReqData {
                 accessor,
                 field_type,
-                column_block_accessor: Default::default(),
                 name: agg_name.to_string(),
                 collecting_for: StatsType::Percentiles,
                 missing: percentiles_req.missing,
@@ -753,6 +731,7 @@ fn build_nodes(
                 segment_reader: reader.clone(),
                 evaluator,
                 matching_docs_buffer,
+                is_top_level,
             });
             let children = build_children(&req.sub_aggregation, reader, segment_ordinal, data)?;
             Ok(vec![AggRefNode {
@@ -895,7 +874,7 @@ fn build_terms_or_cardinality_nodes(
         });
     }
 
-    // Add one node per accessor to mirror previous behavior and allow per-type missing handling.
+    // Add one node per accessor
     for (accessor, column_type) in column_and_types {
         let missing_value_for_accessor = if use_special_missing_agg {
             None
@@ -926,11 +905,8 @@ fn build_terms_or_cardinality_nodes(
                     column_type,
                     str_dict_column: str_dict_column.clone(),
                     missing_value_for_accessor,
-                    column_block_accessor: Default::default(),
                     name: agg_name.to_string(),
                     req: TermsAggregationInternal::from_req(req),
-                    // Will be filled later when building collectors
-                    sub_aggregation_blueprint: None,
                     sug_aggregations: sub_aggs.clone(),
                     allowed_term_ids,
                     is_top_level,
@@ -943,7 +919,6 @@ fn build_terms_or_cardinality_nodes(
                     column_type,
                     str_dict_column: str_dict_column.clone(),
                     missing_value_for_accessor,
-                    column_block_accessor: Default::default(),
                     name: agg_name.to_string(),
                     req: req.clone(),
                 });

src/aggregation/agg_tests.rs

@@ -2,15 +2,441 @@ use serde_json::Value;
 
 use crate::aggregation::agg_req::{Aggregation, Aggregations};
 use crate::aggregation::agg_result::AggregationResults;
-use crate::aggregation::buf_collector::DOC_BLOCK_SIZE;
 use crate::aggregation::collector::AggregationCollector;
 use crate::aggregation::intermediate_agg_result::IntermediateAggregationResults;
 use crate::aggregation::tests::{get_test_index_2_segments, get_test_index_from_values_and_terms};
 use crate::aggregation::DistributedAggregationCollector;
+use crate::docset::COLLECT_BLOCK_BUFFER_LEN;
 use crate::query::{AllQuery, TermQuery};
 use crate::schema::{IndexRecordOption, Schema, FAST};
 use crate::{Index, IndexWriter, Term};
 
+// The following tests ensure that each bucket aggregation type correctly functions as a
+// sub-aggregation of another bucket aggregation in two scenarios:
+// 1) The parent has more buckets than the child sub-aggregation
+// 2) The child sub-aggregation has more buckets than the parent
+//
+// These scenarios exercise the bucket id mapping and sub-aggregation routing logic.
+
+#[test]
+fn test_terms_as_subagg_parent_more_vs_child_more() -> crate::Result<()> {
+    let index = get_test_index_2_segments(false)?;
+
+    // Case A: parent has more buckets than child
+    // Parent: range with 4 buckets
+    // Child: terms on text -> 2 buckets
+    let agg_parent_more: Aggregations = serde_json::from_value(json!({
+        "parent_range": {
+            "range": {
+                "field": "score",
+                "ranges": [
+                    {"to": 3.0},
+                    {"from": 3.0, "to": 7.0},
+                    {"from": 7.0, "to": 20.0},
+                    {"from": 20.0}
+                ]
+            },
+            "aggs": {
+                "child_terms": {"terms": {"field": "text", "order": {"_key": "asc"}}}
+            }
+        }
+    }))
+    .unwrap();
+
+    let res = crate::aggregation::tests::exec_request(agg_parent_more, &index)?;
+    // Exact expected structure and counts
+    assert_eq!(
+        res["parent_range"]["buckets"],
+        json!([
+            {
+                "key": "*-3",
+                "doc_count": 1,
+                "to": 3.0,
+                "child_terms": {
+                    "buckets": [
+                        {"doc_count": 1, "key": "cool"}
+                    ],
+                    "sum_other_doc_count": 0
+                }
+            },
+            {
+                "key": "3-7",
+                "doc_count": 3,
+                "from": 3.0,
+                "to": 7.0,
+                "child_terms": {
+                    "buckets": [
+                        {"doc_count": 2, "key": "cool"},
+                        {"doc_count": 1, "key": "nohit"}
+                    ],
+                    "sum_other_doc_count": 0
+                }
+            },
+            {
+                "key": "7-20",
+                "doc_count": 3,
+                "from": 7.0,
+                "to": 20.0,
+                "child_terms": {
+                    "buckets": [
+                        {"doc_count": 3, "key": "cool"}
+                    ],
+                    "sum_other_doc_count": 0
+                }
+            },
+            {
+                "key": "20-*",
+                "doc_count": 2,
+                "from": 20.0,
+                "child_terms": {
+                    "buckets": [
+                        {"doc_count": 1, "key": "cool"},
+                        {"doc_count": 1, "key": "nohit"}
+                    ],
+                    "sum_other_doc_count": 0
+                }
+            }
+        ])
+    );
+
+    // Case B: child has more buckets than parent
+    // Parent: histogram on score with large interval -> 1 bucket
+    // Child: terms on text -> 2 buckets (cool/nohit)
+    let agg_child_more: Aggregations = serde_json::from_value(json!({
+        "parent_hist": {
+            "histogram": {"field": "score", "interval": 100.0},
+            "aggs": {
+                "child_terms": {"terms": {"field": "text", "order": {"_key": "asc"}}}
+            }
+        }
+    }))
+    .unwrap();
+
+    let res = crate::aggregation::tests::exec_request(agg_child_more, &index)?;
+    assert_eq!(
+        res["parent_hist"],
+        json!({
+            "buckets": [
+                {
+                    "key": 0.0,
+                    "doc_count": 9,
+                    "child_terms": {
+                        "buckets": [
+                            {"doc_count": 7, "key": "cool"},
+                            {"doc_count": 2, "key": "nohit"}
+                        ],
+                        "sum_other_doc_count": 0
+                    }
+                }
+            ]
+        })
+    );
+
+    Ok(())
+}
+
+#[test]
+fn test_range_as_subagg_parent_more_vs_child_more() -> crate::Result<()> {
+    let index = get_test_index_2_segments(false)?;
+
+    // Case A: parent has more buckets than child
+    // Parent: range with 5 buckets
+    // Child: coarse range with 3 buckets
+    let agg_parent_more: Aggregations = serde_json::from_value(json!({
+        "parent_range": {
+            "range": {
+                "field": "score",
+                "ranges": [
+                    {"to": 3.0},
+                    {"from": 3.0, "to": 7.0},
+                    {"from": 7.0, "to": 11.0},
+                    {"from": 11.0, "to": 20.0},
+                    {"from": 20.0}
+                ]
+            },
+            "aggs": {
+                "child_range": {
+                    "range": {
+                        "field": "score",
+                        "ranges": [
+                            {"to": 3.0},
+                            {"from": 3.0, "to": 20.0}
+                        ]
+                    }
+                }
+            }
+        }
+    }))
+    .unwrap();
+    let res = crate::aggregation::tests::exec_request(agg_parent_more, &index)?;
+    assert_eq!(
+        res["parent_range"]["buckets"],
+        json!([
+            {"key": "*-3", "doc_count": 1, "to": 3.0,
+                "child_range": {"buckets": [
+                    {"key": "*-3", "doc_count": 1, "to": 3.0},
+                    {"key": "3-20", "doc_count": 0, "from": 3.0, "to": 20.0},
+                    {"key": "20-*", "doc_count": 0, "from": 20.0}
+                ]}
+            },
+            {"key": "3-7", "doc_count": 3, "from": 3.0, "to": 7.0,
+                "child_range": {"buckets": [
+                    {"key": "*-3", "doc_count": 0, "to": 3.0},
+                    {"key": "3-20", "doc_count": 3, "from": 3.0, "to": 20.0},
+                    {"key": "20-*", "doc_count": 0, "from": 20.0}
+                ]}
+            },
+            {"key": "7-11", "doc_count": 1, "from": 7.0, "to": 11.0,
+                "child_range": {"buckets": [
+                    {"key": "*-3", "doc_count": 0, "to": 3.0},
+                    {"key": "3-20", "doc_count": 1, "from": 3.0, "to": 20.0},
+                    {"key": "20-*", "doc_count": 0, "from": 20.0}
+                ]}
+            },
+            {"key": "11-20", "doc_count": 2, "from": 11.0, "to": 20.0,
+                "child_range": {"buckets": [
+                    {"key": "*-3", "doc_count": 0, "to": 3.0},
+                    {"key": "3-20", "doc_count": 2, "from": 3.0, "to": 20.0},
+                    {"key": "20-*", "doc_count": 0, "from": 20.0}
+                ]}
+            },
+            {"key": "20-*", "doc_count": 2, "from": 20.0,
+                "child_range": {"buckets": [
+                    {"key": "*-3", "doc_count": 0, "to": 3.0},
+                    {"key": "3-20", "doc_count": 0, "from": 3.0, "to": 20.0},
+                    {"key": "20-*", "doc_count": 2, "from": 20.0}
+                ]}
+            }
+        ])
+    );
+
+    // Case B: child has more buckets than parent
+    // Parent: terms on text (2 buckets)
+    // Child: range with 4 buckets
+    let agg_child_more: Aggregations = serde_json::from_value(json!({
+        "parent_terms": {
+            "terms": {"field": "text"},
+            "aggs": {
+                "child_range": {
+                    "range": {
+                        "field": "score",
+                        "ranges": [
+                            {"to": 3.0},
+                            {"from": 3.0, "to": 7.0},
+                            {"from": 7.0, "to": 20.0}
+                        ]
+                    }
+                }
+            }
+        }
+    }))
+    .unwrap();
+    let res = crate::aggregation::tests::exec_request(agg_child_more, &index)?;
+
+    assert_eq!(
+        res["parent_terms"],
+        json!({
+            "buckets": [
+                {
+                    "key": "cool",
+                    "doc_count": 7,
+                    "child_range": {
+                        "buckets": [
+                            {"key": "*-3", "doc_count": 1, "to": 3.0},
+                            {"key": "3-7", "doc_count": 2, "from": 3.0, "to": 7.0},
+                            {"key": "7-20", "doc_count": 3, "from": 7.0, "to": 20.0},
+                            {"key": "20-*", "doc_count": 1, "from": 20.0}
+                        ]
+                    }
+                },
+                {
+                    "key": "nohit",
+                    "doc_count": 2,
+                    "child_range": {
+                        "buckets": [
+                            {"key": "*-3", "doc_count": 0, "to": 3.0},
+                            {"key": "3-7", "doc_count": 1, "from": 3.0, "to": 7.0},
+                            {"key": "7-20", "doc_count": 0, "from": 7.0, "to": 20.0},
+                            {"key": "20-*", "doc_count": 1, "from": 20.0}
+                        ]
+                    }
+                }
+            ],
+            "doc_count_error_upper_bound": 0,
+            "sum_other_doc_count": 0
+        })
+    );
+
+    Ok(())
+}
+
+#[test]
+fn test_histogram_as_subagg_parent_more_vs_child_more() -> crate::Result<()> {
+    let index = get_test_index_2_segments(false)?;
+
+    // Case A: parent has more buckets than child
+    // Parent: range with several ranges
+    // Child: histogram with large interval (single bucket per parent)
+    let agg_parent_more: Aggregations = serde_json::from_value(json!({
+        "parent_range": {
+            "range": {
+                "field": "score",
+                "ranges": [
+                    {"to": 3.0},
+                    {"from": 3.0, "to": 7.0},
+                    {"from": 7.0, "to": 11.0},
+                    {"from": 11.0, "to": 20.0},
+                    {"from": 20.0}
+                ]
+            },
+            "aggs": {
+                "child_hist": {"histogram": {"field": "score", "interval": 100.0}}
+            }
+        }
+    }))
+    .unwrap();
+    let res = crate::aggregation::tests::exec_request(agg_parent_more, &index)?;
+    assert_eq!(
+        res["parent_range"]["buckets"],
+        json!([
+            {"key": "*-3", "doc_count": 1, "to": 3.0,
+                "child_hist": {"buckets": [ {"key": 0.0, "doc_count": 1} ]}
+            },
+            {"key": "3-7", "doc_count": 3, "from": 3.0, "to": 7.0,
+                "child_hist": {"buckets": [ {"key": 0.0, "doc_count": 3} ]}
+            },
+            {"key": "7-11", "doc_count": 1, "from": 7.0, "to": 11.0,
+                "child_hist": {"buckets": [ {"key": 0.0, "doc_count": 1} ]}
+            },
+            {"key": "11-20", "doc_count": 2, "from": 11.0, "to": 20.0,
+                "child_hist": {"buckets": [ {"key": 0.0, "doc_count": 2} ]}
+            },
+            {"key": "20-*", "doc_count": 2, "from": 20.0,
+                "child_hist": {"buckets": [ {"key": 0.0, "doc_count": 2} ]}
+            }
+        ])
+    );
+
+    // Case B: child has more buckets than parent
+    // Parent: terms on text -> 2 buckets
+    // Child: histogram with small interval -> multiple buckets including empties
+    let agg_child_more: Aggregations = serde_json::from_value(json!({
+        "parent_terms": {
+            "terms": {"field": "text"},
+            "aggs": {
+                "child_hist": {"histogram": {"field": "score", "interval": 10.0}}
+            }
+        }
+    }))
+    .unwrap();
+    let res = crate::aggregation::tests::exec_request(agg_child_more, &index)?;
+    assert_eq!(
+        res["parent_terms"],
+        json!({
+            "buckets": [
+                {
+                    "key": "cool",
+                    "doc_count": 7,
+                    "child_hist": {
+                        "buckets": [
+                            {"key": 0.0, "doc_count": 4},
+                            {"key": 10.0, "doc_count": 2},
+                            {"key": 20.0, "doc_count": 0},
+                            {"key": 30.0, "doc_count": 0},
+                            {"key": 40.0, "doc_count": 1}
+                        ]
+                    }
+                },
+                {
+                    "key": "nohit",
+                    "doc_count": 2,
+                    "child_hist": {
+                        "buckets": [
+                            {"key": 0.0, "doc_count": 1},
+                            {"key": 10.0, "doc_count": 0},
+                            {"key": 20.0, "doc_count": 0},
+                            {"key": 30.0, "doc_count": 0},
+                            {"key": 40.0, "doc_count": 1}
+                        ]
+                    }
+                }
+            ],
+            "doc_count_error_upper_bound": 0,
+            "sum_other_doc_count": 0
+        })
+    );
+
+    Ok(())
+}
+
+#[test]
+fn test_date_histogram_as_subagg_parent_more_vs_child_more() -> crate::Result<()> {
+    let index = get_test_index_2_segments(false)?;
+
+    // Case A: parent has more buckets than child
+    // Parent: range with several buckets
+    // Child: date_histogram with 30d -> single bucket per parent
+    let agg_parent_more: Aggregations = serde_json::from_value(json!({
+        "parent_range": {
+            "range": {
+                "field": "score",
+                "ranges": [
+                    {"to": 3.0},
+                    {"from": 3.0, "to": 7.0},
+                    {"from": 7.0, "to": 11.0},
+                    {"from": 11.0, "to": 20.0},
+                    {"from": 20.0}
+                ]
+            },
+            "aggs": {
+                "child_date_hist": {"date_histogram": {"field": "date", "fixed_interval": "30d"}}
+            }
+        }
+    }))
+    .unwrap();
+    let res = crate::aggregation::tests::exec_request(agg_parent_more, &index)?;
+    let buckets = res["parent_range"]["buckets"].as_array().unwrap();
+    // Verify each parent bucket has exactly one child date bucket with matching doc_count
+    for bucket in buckets {
+        let parent_count = bucket["doc_count"].as_u64().unwrap();
+        let child_buckets = bucket["child_date_hist"]["buckets"].as_array().unwrap();
+        assert_eq!(child_buckets.len(), 1);
+        assert_eq!(child_buckets[0]["doc_count"], parent_count);
+    }
+
+    // Case B: child has more buckets than parent
+    // Parent: terms on text (2 buckets)
+    // Child: date_histogram with 1d -> multiple buckets
+    let agg_child_more: Aggregations = serde_json::from_value(json!({
+        "parent_terms": {
+            "terms": {"field": "text"},
+            "aggs": {
+                "child_date_hist": {"date_histogram": {"field": "date", "fixed_interval": "1d"}}
+            }
+        }
+    }))
+    .unwrap();
+    let res = crate::aggregation::tests::exec_request(agg_child_more, &index)?;
+    let buckets = res["parent_terms"]["buckets"].as_array().unwrap();
+
+    // cool bucket
+    assert_eq!(buckets[0]["key"], "cool");
+    let cool_buckets = buckets[0]["child_date_hist"]["buckets"].as_array().unwrap();
+    assert_eq!(cool_buckets.len(), 3);
+    assert_eq!(cool_buckets[0]["doc_count"], 1); // day 0
+    assert_eq!(cool_buckets[1]["doc_count"], 4); // day 1
+    assert_eq!(cool_buckets[2]["doc_count"], 2); // day 2
+
+    // nohit bucket
+    assert_eq!(buckets[1]["key"], "nohit");
+    let nohit_buckets = buckets[1]["child_date_hist"]["buckets"].as_array().unwrap();
+    assert_eq!(nohit_buckets.len(), 2);
+    assert_eq!(nohit_buckets[0]["doc_count"], 1); // day 1
+    assert_eq!(nohit_buckets[1]["doc_count"], 1); // day 2
+
+    Ok(())
+}
+
 fn get_avg_req(field_name: &str) -> Aggregation {
     serde_json::from_value(json!({
         "avg": {
@@ -25,6 +451,10 @@ fn get_collector(agg_req: Aggregations) -> AggregationCollector {
 }
 
 // *** EVERY BUCKET-TYPE SHOULD BE TESTED HERE ***
+// Note: The flushng part of these  tests are outdated, since the buffering change after converting
+// the collection into one collector per request instead of per bucket.
+//
+// However they are useful as they test a complex aggregation requests.
 fn test_aggregation_flushing(
     merge_segments: bool,
     use_distributed_collector: bool,
@@ -37,8 +467,9 @@ fn test_aggregation_flushing(
 
     let reader = index.reader()?;
 
-    assert_eq!(DOC_BLOCK_SIZE, 64);
+    assert_eq!(COLLECT_BLOCK_BUFFER_LEN, 64);
-    // In the tree we cache Documents of DOC_BLOCK_SIZE, before passing them down as one block.
+    // In the tree we cache documents of COLLECT_BLOCK_BUFFER_LEN before passing them down as one
+    // block.
     //
     // Build a request so that on the first level we have one full cache, which is then flushed.
     // The same cache should have some residue docs at the end, which are flushed (Range 0-70)

src/aggregation/bucket/filter.rs

@@ -6,10 +6,14 @@ use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use crate::aggregation::agg_data::{
     build_segment_agg_collectors, AggRefNode, AggregationsSegmentCtx,
 };
+use crate::aggregation::cached_sub_aggs::{
+    CachedSubAggs, HighCardSubAggCache, LowCardSubAggCache, SubAggCache,
+};
 use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateAggregationResults, IntermediateBucketResult,
 };
-use crate::aggregation::segment_agg_result::{CollectorClone, SegmentAggregationCollector};
+use crate::aggregation::segment_agg_result::{BucketIdProvider, SegmentAggregationCollector};
+use crate::aggregation::BucketId;
 use crate::docset::DocSet;
 use crate::query::{AllQuery, EnableScoring, Query, QueryParser};
 use crate::schema::Schema;
@@ -404,15 +408,18 @@ pub struct FilterAggReqData {
     pub evaluator: DocumentQueryEvaluator,
     /// Reusable buffer for matching documents to minimize allocations during collection
     pub matching_docs_buffer: Vec<DocId>,
+    /// True if this filter aggregation is at the top level of the aggregation tree (not nested).
+    pub is_top_level: bool,
 }
 
 impl FilterAggReqData {
     pub(crate) fn get_memory_consumption(&self) -> usize {
         // Estimate: name + segment reader reference + bitset + buffer capacity
         self.name.len()
-            + std::mem::size_of::<SegmentReader>()
+        + std::mem::size_of::<SegmentReader>()
-            + self.evaluator.bitset.len() / 8 // BitSet memory (bits to bytes)
+        + self.evaluator.bitset.len() / 8 // BitSet memory (bits to bytes)
-            + self.matching_docs_buffer.capacity() * std::mem::size_of::<DocId>()
+        + self.matching_docs_buffer.capacity() * std::mem::size_of::<DocId>()
+        + std::mem::size_of::<bool>()
     }
 }
 
@@ -446,7 +453,7 @@ impl DocumentQueryEvaluator {
         let weight = query.weight(EnableScoring::disabled_from_schema(&schema))?;
 
         // Get a scorer that iterates over matching documents
-        let mut scorer = weight.scorer(segment_reader, 1.0, 0)?;
+        let mut scorer = weight.scorer(segment_reader, 1.0)?;
 
         // Create a BitSet to hold all matching documents
         let mut bitset = BitSet::with_max_value(max_doc);
@@ -489,17 +496,24 @@ impl Debug for DocumentQueryEvaluator {
     }
 }
 
-/// Segment collector for filter aggregation
+#[derive(Debug, Clone, PartialEq, Copy)]
-pub struct SegmentFilterCollector {
+struct DocCount {
-    /// Document count in this bucket
     doc_count: u64,
+    bucket_id: BucketId,
+}
+
+/// Segment collector for filter aggregation
+pub struct SegmentFilterCollector<C: SubAggCache> {
+    /// Document counts per parent bucket
+    parent_buckets: Vec<DocCount>,
     /// Sub-aggregation collectors
-    sub_aggregations: Option<Box<dyn SegmentAggregationCollector>>,
+    sub_aggregations: Option<CachedSubAggs<C>>,
+    bucket_id_provider: BucketIdProvider,
     /// Accessor index for this filter aggregation (to access FilterAggReqData)
     accessor_idx: usize,
 }
 
-impl SegmentFilterCollector {
+impl<C: SubAggCache> SegmentFilterCollector<C> {
     /// Create a new filter segment collector following the new agg_data pattern
     pub(crate) fn from_req_and_validate(
         req: &mut AggregationsSegmentCtx,
@@ -511,47 +525,75 @@ impl SegmentFilterCollector {
         } else {
             None
         };
+        let sub_agg_collector = sub_agg_collector.map(CachedSubAggs::new);
 
         Ok(SegmentFilterCollector {
-            doc_count: 0,
+            parent_buckets: Vec::new(),
             sub_aggregations: sub_agg_collector,
             accessor_idx: node.idx_in_req_data,
+            bucket_id_provider: BucketIdProvider::default(),
         })
     }
 }
 
-impl Debug for SegmentFilterCollector {
+pub(crate) fn build_segment_filter_collector(
+    req: &mut AggregationsSegmentCtx,
+    node: &AggRefNode,
+) -> crate::Result<Box<dyn SegmentAggregationCollector>> {
+    let is_top_level = req.per_request.filter_req_data[node.idx_in_req_data]
+        .as_ref()
+        .expect("filter_req_data slot is empty")
+        .is_top_level;
+
+    if is_top_level {
+        Ok(Box::new(
+            SegmentFilterCollector::<LowCardSubAggCache>::from_req_and_validate(req, node)?,
+        ))
+    } else {
+        Ok(Box::new(
+            SegmentFilterCollector::<HighCardSubAggCache>::from_req_and_validate(req, node)?,
+        ))
+    }
+}
+
+impl<C: SubAggCache> Debug for SegmentFilterCollector<C> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         f.debug_struct("SegmentFilterCollector")
-            .field("doc_count", &self.doc_count)
+            .field("buckets", &self.parent_buckets)
             .field("has_sub_aggs", &self.sub_aggregations.is_some())
             .field("accessor_idx", &self.accessor_idx)
             .finish()
     }
 }
 
-impl CollectorClone for SegmentFilterCollector {
+impl<C: SubAggCache> SegmentAggregationCollector for SegmentFilterCollector<C> {
-    fn clone_box(&self) -> Box<dyn SegmentAggregationCollector> {
-        // For now, panic - this needs proper implementation with weight recreation
-        panic!("SegmentFilterCollector cloning not yet implemented - requires weight recreation")
-    }
-}
-
-impl SegmentAggregationCollector for SegmentFilterCollector {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
         let mut sub_results = IntermediateAggregationResults::default();
+        let bucket_opt = self.parent_buckets.get(parent_bucket_id as usize);
 
-        if let Some(sub_aggs) = self.sub_aggregations {
+        if let Some(sub_aggs) = &mut self.sub_aggregations {
-            sub_aggs.add_intermediate_aggregation_result(agg_data, &mut sub_results)?;
+            sub_aggs
+                .get_sub_agg_collector()
+                .add_intermediate_aggregation_result(
+                    agg_data,
+                    &mut sub_results,
+                    // Here we create a new bucket ID for sub-aggregations if the bucket doesn't
+                    // exist, so that sub-aggregations can still produce results (e.g., zero doc
+                    // count)
+                    bucket_opt
+                        .map(|bucket| bucket.bucket_id)
+                        .unwrap_or(self.bucket_id_provider.next_bucket_id()),
+                )?;
         }
 
         // Create the filter bucket result
         let filter_bucket_result = IntermediateBucketResult::Filter {
-            doc_count: self.doc_count,
+            doc_count: bucket_opt.map(|b| b.doc_count).unwrap_or(0),
             sub_aggregations: sub_results,
         };
 
@@ -570,32 +612,17 @@ impl SegmentAggregationCollector for SegmentFilterCollector {
         Ok(())
     }
 
-    fn collect(&mut self, doc: DocId, agg_data: &mut AggregationsSegmentCtx) -> crate::Result<()> {
+    fn collect(
-        // Access the evaluator from FilterAggReqData
-        let req_data = agg_data.get_filter_req_data(self.accessor_idx);
-
-        // O(1) BitSet lookup to check if document matches filter
-        if req_data.evaluator.matches_document(doc) {
-            self.doc_count += 1;
-
-            // If we have sub-aggregations, collect on them for this filtered document
-            if let Some(sub_aggs) = &mut self.sub_aggregations {
-                sub_aggs.collect(doc, agg_data)?;
-            }
-        }
-        Ok(())
-    }
-
-    #[inline]
-    fn collect_block(
         &mut self,
-        docs: &[DocId],
+        parent_bucket_id: BucketId,
+        docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
         if docs.is_empty() {
             return Ok(());
         }
 
+        let mut bucket = self.parent_buckets[parent_bucket_id as usize];
         // Take the request data to avoid borrow checker issues with sub-aggregations
         let mut req = agg_data.take_filter_req_data(self.accessor_idx);
 
@@ -604,18 +631,24 @@ impl SegmentAggregationCollector for SegmentFilterCollector {
         req.evaluator
             .filter_batch(docs, &mut req.matching_docs_buffer);
 
-        self.doc_count += req.matching_docs_buffer.len() as u64;
+        bucket.doc_count += req.matching_docs_buffer.len() as u64;
 
         // Batch process sub-aggregations if we have matches
         if !req.matching_docs_buffer.is_empty() {
             if let Some(sub_aggs) = &mut self.sub_aggregations {
-                // Use collect_block for better sub-aggregation performance
+                for &doc_id in &req.matching_docs_buffer {
-                sub_aggs.collect_block(&req.matching_docs_buffer, agg_data)?;
+                    sub_aggs.push(bucket.bucket_id, doc_id);
+                }
             }
         }
 
         // Put the request data back
         agg_data.put_back_filter_req_data(self.accessor_idx, req);
+        if let Some(sub_aggs) = &mut self.sub_aggregations {
+            sub_aggs.check_flush_local(agg_data)?;
+        }
+        // put back bucket
+        self.parent_buckets[parent_bucket_id as usize] = bucket;
 
         Ok(())
     }
@@ -626,6 +659,21 @@ impl SegmentAggregationCollector for SegmentFilterCollector {
         }
         Ok(())
     }
+
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        _agg_data: &AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        while self.parent_buckets.len() <= max_bucket as usize {
+            let bucket_id = self.bucket_id_provider.next_bucket_id();
+            self.parent_buckets.push(DocCount {
+                doc_count: 0,
+                bucket_id,
+            });
+        }
+        Ok(())
+    }
 }
 
 /// Intermediate result for filter aggregation
@@ -1519,9 +1567,9 @@ mod tests {
         let searcher = reader.searcher();
 
         let agg = json!({
-            "test": {
+                "test": {
-                "filter": deserialized,
+                    "filter": deserialized,
-                "aggs": { "count": { "value_count": { "field": "brand" } } }
+                    "aggs": { "count": { "value_count": { "field": "brand" } } }
             }
         });
 

src/aggregation/bucket/histogram/histogram.rs

@@ -1,6 +1,6 @@
 use std::cmp::Ordering;
 
-use columnar::{Column, ColumnBlockAccessor, ColumnType};
+use columnar::{Column, ColumnType};
 use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 use tantivy_bitpacker::minmax;
@@ -8,14 +8,14 @@ use tantivy_bitpacker::minmax;
 use crate::aggregation::agg_data::{
     build_segment_agg_collectors, AggRefNode, AggregationsSegmentCtx,
 };
-use crate::aggregation::agg_limits::MemoryConsumption;
 use crate::aggregation::agg_req::Aggregations;
 use crate::aggregation::agg_result::BucketEntry;
+use crate::aggregation::cached_sub_aggs::{CachedSubAggs, HighCardCachedSubAggs};
 use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateAggregationResults, IntermediateBucketResult,
     IntermediateHistogramBucketEntry,
 };
-use crate::aggregation::segment_agg_result::SegmentAggregationCollector;
+use crate::aggregation::segment_agg_result::{BucketIdProvider, SegmentAggregationCollector};
 use crate::aggregation::*;
 use crate::TantivyError;
 
@@ -26,13 +26,8 @@ pub struct HistogramAggReqData {
     pub accessor: Column<u64>,
     /// The field type of the fast field.
     pub field_type: ColumnType,
-    /// The column block accessor to access the fast field values.
-    pub column_block_accessor: ColumnBlockAccessor<u64>,
     /// The name of the aggregation.
     pub name: String,
-    /// The sub aggregation blueprint, used to create sub aggregations for each bucket.
-    /// Will be filled during initialization of the collector.
-    pub sub_aggregation_blueprint: Option<Box<dyn SegmentAggregationCollector>>,
     /// The histogram aggregation request.
     pub req: HistogramAggregation,
     /// True if this is a date_histogram aggregation.
@@ -257,18 +252,24 @@ impl HistogramBounds {
 pub(crate) struct SegmentHistogramBucketEntry {
     pub key: f64,
     pub doc_count: u64,
+    pub bucket_id: BucketId,
 }
 
 impl SegmentHistogramBucketEntry {
     pub(crate) fn into_intermediate_bucket_entry(
         self,
-        sub_aggregation: Option<Box<dyn SegmentAggregationCollector>>,
+        sub_aggregation: &mut Option<HighCardCachedSubAggs>,
         agg_data: &AggregationsSegmentCtx,
     ) -> crate::Result<IntermediateHistogramBucketEntry> {
         let mut sub_aggregation_res = IntermediateAggregationResults::default();
         if let Some(sub_aggregation) = sub_aggregation {
             sub_aggregation
-                .add_intermediate_aggregation_result(agg_data, &mut sub_aggregation_res)?;
+                .get_sub_agg_collector()
+                .add_intermediate_aggregation_result(
+                    agg_data,
+                    &mut sub_aggregation_res,
+                    self.bucket_id,
+                )?;
         }
         Ok(IntermediateHistogramBucketEntry {
             key: self.key,
@@ -278,27 +279,38 @@ impl SegmentHistogramBucketEntry {
     }
 }
 
+#[derive(Clone, Debug, Default)]
+struct HistogramBuckets {
+    pub buckets: FxHashMap<i64, SegmentHistogramBucketEntry>,
+}
+
 /// The collector puts values from the fast field into the correct buckets and does a conversion to
 /// the correct datatype.
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 pub struct SegmentHistogramCollector {
     /// The buckets containing the aggregation data.
-    buckets: FxHashMap<i64, SegmentHistogramBucketEntry>,
+    /// One Histogram bucket per parent bucket id.
-    sub_aggregations: FxHashMap<i64, Box<dyn SegmentAggregationCollector>>,
+    parent_buckets: Vec<HistogramBuckets>,
+    sub_agg: Option<HighCardCachedSubAggs>,
     accessor_idx: usize,
+    bucket_id_provider: BucketIdProvider,
 }
 
 impl SegmentAggregationCollector for SegmentHistogramCollector {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
         let name = agg_data
             .get_histogram_req_data(self.accessor_idx)
             .name
             .clone();
-        let bucket = self.into_intermediate_bucket_result(agg_data)?;
+        // TODO: avoid prepare_max_bucket here and handle empty buckets.
+        self.prepare_max_bucket(parent_bucket_id, agg_data)?;
+        let histogram = std::mem::take(&mut self.parent_buckets[parent_bucket_id as usize]);
+        let bucket = self.add_intermediate_bucket_result(agg_data, histogram)?;
         results.push(name, IntermediateAggregationResult::Bucket(bucket))?;
 
         Ok(())
@@ -307,44 +319,40 @@ impl SegmentAggregationCollector for SegmentHistogramCollector {
     #[inline]
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        self.collect_block(&[doc], agg_data)
-    }
-
-    #[inline]
-    fn collect_block(
-        &mut self,
         docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        let mut req = agg_data.take_histogram_req_data(self.accessor_idx);
+        let req = agg_data.take_histogram_req_data(self.accessor_idx);
         let mem_pre = self.get_memory_consumption();
+        let buckets = &mut self.parent_buckets[parent_bucket_id as usize].buckets;
 
         let bounds = req.bounds;
         let interval = req.req.interval;
         let offset = req.offset;
         let get_bucket_pos = |val| get_bucket_pos_f64(val, interval, offset) as i64;
 
-        req.column_block_accessor.fetch_block(docs, &req.accessor);
+        agg_data
-        for (doc, val) in req
+            .column_block_accessor
+            .fetch_block(docs, &req.accessor);
+        for (doc, val) in agg_data
             .column_block_accessor
             .iter_docid_vals(docs, &req.accessor)
         {
-            let val = f64_from_fastfield_u64(val, &req.field_type);
+            let val = f64_from_fastfield_u64(val, req.field_type);
             let bucket_pos = get_bucket_pos(val);
             if bounds.contains(val) {
-                let bucket = self.buckets.entry(bucket_pos).or_insert_with(|| {
+                let bucket = buckets.entry(bucket_pos).or_insert_with(|| {
                     let key = get_bucket_key_from_pos(bucket_pos as f64, interval, offset);
-                    SegmentHistogramBucketEntry { key, doc_count: 0 }
+                    SegmentHistogramBucketEntry {
+                        key,
+                        doc_count: 0,
+                        bucket_id: self.bucket_id_provider.next_bucket_id(),
+                    }
                 });
                 bucket.doc_count += 1;
-                if let Some(sub_aggregation_blueprint) = req.sub_aggregation_blueprint.as_ref() {
+                if let Some(sub_agg) = &mut self.sub_agg {
-                    self.sub_aggregations
+                    sub_agg.push(bucket.bucket_id, doc);
-                        .entry(bucket_pos)
-                        .or_insert_with(|| sub_aggregation_blueprint.clone())
-                        .collect(doc, agg_data)?;
                 }
             }
         }
@@ -358,14 +366,30 @@ impl SegmentAggregationCollector for SegmentHistogramCollector {
                 .add_memory_consumed(mem_delta as u64)?;
         }
 
+        if let Some(sub_agg) = &mut self.sub_agg {
+            sub_agg.check_flush_local(agg_data)?;
+        }
+
         Ok(())
     }
 
     fn flush(&mut self, agg_data: &mut AggregationsSegmentCtx) -> crate::Result<()> {
-        for sub_aggregation in self.sub_aggregations.values_mut() {
+        if let Some(sub_aggregation) = &mut self.sub_agg {
             sub_aggregation.flush(agg_data)?;
         }
+        Ok(())
+    }
 
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        _agg_data: &AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        while self.parent_buckets.len() <= max_bucket as usize {
+            self.parent_buckets.push(HistogramBuckets {
+                buckets: FxHashMap::default(),
+            });
+        }
         Ok(())
     }
 }
@@ -373,22 +397,19 @@ impl SegmentAggregationCollector for SegmentHistogramCollector {
 impl SegmentHistogramCollector {
     fn get_memory_consumption(&self) -> usize {
         let self_mem = std::mem::size_of::<Self>();
-        let sub_aggs_mem = self.sub_aggregations.memory_consumption();
+        let buckets_mem = self.parent_buckets.len() * std::mem::size_of::<HistogramBuckets>();
-        let buckets_mem = self.buckets.memory_consumption();
+        self_mem + buckets_mem
-        self_mem + sub_aggs_mem + buckets_mem
     }
     /// Converts the collector result into a intermediate bucket result.
-    pub fn into_intermediate_bucket_result(
+    fn add_intermediate_bucket_result(
-        self,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
+        histogram: HistogramBuckets,
     ) -> crate::Result<IntermediateBucketResult> {
-        let mut buckets = Vec::with_capacity(self.buckets.len());
+        let mut buckets = Vec::with_capacity(histogram.buckets.len());
 
-        for (bucket_pos, bucket) in self.buckets {
+        for bucket in histogram.buckets.into_values() {
-            let bucket_res = bucket.into_intermediate_bucket_entry(
+            let bucket_res = bucket.into_intermediate_bucket_entry(&mut self.sub_agg, agg_data);
-                self.sub_aggregations.get(&bucket_pos).cloned(),
-                agg_data,
-            );
 
             buckets.push(bucket_res?);
         }
@@ -408,7 +429,7 @@ impl SegmentHistogramCollector {
         agg_data: &mut AggregationsSegmentCtx,
         node: &AggRefNode,
     ) -> crate::Result<Self> {
-        let blueprint = if !node.children.is_empty() {
+        let sub_agg = if !node.children.is_empty() {
             Some(build_segment_agg_collectors(agg_data, &node.children)?)
         } else {
             None
@@ -423,13 +444,13 @@ impl SegmentHistogramCollector {
             max: f64::MAX,
         });
         req_data.offset = req_data.req.offset.unwrap_or(0.0);
-
+        let sub_agg = sub_agg.map(CachedSubAggs::new);
-        req_data.sub_aggregation_blueprint = blueprint;
 
         Ok(Self {
-            buckets: Default::default(),
+            parent_buckets: Default::default(),
-            sub_aggregations: Default::default(),
+            sub_agg,
             accessor_idx: node.idx_in_req_data,
+            bucket_id_provider: BucketIdProvider::default(),
         })
     }
 }

src/aggregation/bucket/range.rs

@@ -1,18 +1,22 @@
 use std::fmt::Debug;
 use std::ops::Range;
 
-use columnar::{Column, ColumnBlockAccessor, ColumnType};
+use columnar::{Column, ColumnType};
 use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 
 use crate::aggregation::agg_data::{
     build_segment_agg_collectors, AggRefNode, AggregationsSegmentCtx,
 };
+use crate::aggregation::agg_limits::AggregationLimitsGuard;
+use crate::aggregation::cached_sub_aggs::{
+    CachedSubAggs, HighCardSubAggCache, LowCardCachedSubAggs, LowCardSubAggCache, SubAggCache,
+};
 use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateAggregationResults, IntermediateBucketResult,
     IntermediateRangeBucketEntry, IntermediateRangeBucketResult,
 };
-use crate::aggregation::segment_agg_result::SegmentAggregationCollector;
+use crate::aggregation::segment_agg_result::{BucketIdProvider, SegmentAggregationCollector};
 use crate::aggregation::*;
 use crate::TantivyError;
 
@@ -23,12 +27,12 @@ pub struct RangeAggReqData {
     pub accessor: Column<u64>,
     /// The type of the fast field.
     pub field_type: ColumnType,
-    /// The column block accessor to access the fast field values.
-    pub column_block_accessor: ColumnBlockAccessor<u64>,
     /// The range aggregation request.
     pub req: RangeAggregation,
     /// The name of the aggregation.
     pub name: String,
+    /// Whether this is a top-level aggregation.
+    pub is_top_level: bool,
 }
 
 impl RangeAggReqData {
@@ -151,19 +155,47 @@ pub(crate) struct SegmentRangeAndBucketEntry {
 
 /// The collector puts values from the fast field into the correct buckets and does a conversion to
 /// the correct datatype.
-#[derive(Clone, Debug)]
+pub struct SegmentRangeCollector<C: SubAggCache> {
-pub struct SegmentRangeCollector {
     /// The buckets containing the aggregation data.
-    buckets: Vec<SegmentRangeAndBucketEntry>,
+    /// One for each ParentBucketId
+    parent_buckets: Vec<Vec<SegmentRangeAndBucketEntry>>,
     column_type: ColumnType,
     pub(crate) accessor_idx: usize,
+    sub_agg: Option<CachedSubAggs<C>>,
+    /// Here things get a bit weird. We need to assign unique bucket ids across all
+    /// parent buckets. So we keep track of the next available bucket id here.
+    /// This allows a kind of flattening of the bucket ids across all parent buckets.
+    /// E.g. in nested aggregations:
+    /// Term Agg -> Range aggregation -> Stats aggregation
+    /// E.g. the Term Agg creates 3 buckets ["INFO", "ERROR", "WARN"], each of these has a Range
+    /// aggregation with 4 buckets. The Range aggregation will create buckets with ids:
+    /// - INFO: 0,1,2,3
+    /// - ERROR: 4,5,6,7
+    /// - WARN: 8,9,10,11
+    ///
+    /// This allows the Stats aggregation to have unique bucket ids to refer to.
+    bucket_id_provider: BucketIdProvider,
+    limits: AggregationLimitsGuard,
 }
 
+impl<C: SubAggCache> Debug for SegmentRangeCollector<C> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("SegmentRangeCollector")
+            .field("parent_buckets_len", &self.parent_buckets.len())
+            .field("column_type", &self.column_type)
+            .field("accessor_idx", &self.accessor_idx)
+            .field("has_sub_agg", &self.sub_agg.is_some())
+            .finish()
+    }
+}
+
+/// TODO: Bad naming, there's also SegmentRangeAndBucketEntry
 #[derive(Clone)]
 pub(crate) struct SegmentRangeBucketEntry {
     pub key: Key,
     pub doc_count: u64,
-    pub sub_aggregation: Option<Box<dyn SegmentAggregationCollector>>,
+    // pub sub_aggregation: Option<Box<dyn SegmentAggregationCollector>>,
+    pub bucket_id: BucketId,
     /// The from range of the bucket. Equals `f64::MIN` when `None`.
     pub from: Option<f64>,
     /// The to range of the bucket. Equals `f64::MAX` when `None`. Open interval, `to` is not
@@ -184,48 +216,50 @@ impl Debug for SegmentRangeBucketEntry {
 impl SegmentRangeBucketEntry {
     pub(crate) fn into_intermediate_bucket_entry(
         self,
-        agg_data: &AggregationsSegmentCtx,
     ) -> crate::Result<IntermediateRangeBucketEntry> {
-        let mut sub_aggregation_res = IntermediateAggregationResults::default();
+        let sub_aggregation = IntermediateAggregationResults::default();
-        if let Some(sub_aggregation) = self.sub_aggregation {
-            sub_aggregation
-                .add_intermediate_aggregation_result(agg_data, &mut sub_aggregation_res)?
-        } else {
-            Default::default()
-        };
 
         Ok(IntermediateRangeBucketEntry {
             key: self.key.into(),
             doc_count: self.doc_count,
-            sub_aggregation: sub_aggregation_res,
+            sub_aggregation_res: sub_aggregation,
             from: self.from,
             to: self.to,
         })
     }
 }
 
-impl SegmentAggregationCollector for SegmentRangeCollector {
+impl<C: SubAggCache> SegmentAggregationCollector for SegmentRangeCollector<C> {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
+        self.prepare_max_bucket(parent_bucket_id, agg_data)?;
         let field_type = self.column_type;
         let name = agg_data
             .get_range_req_data(self.accessor_idx)
             .name
             .to_string();
 
-        let buckets: FxHashMap<SerializedKey, IntermediateRangeBucketEntry> = self
+        let buckets = std::mem::take(&mut self.parent_buckets[parent_bucket_id as usize]);
-            .buckets
+
+        let buckets: FxHashMap<SerializedKey, IntermediateRangeBucketEntry> = buckets
             .into_iter()
-            .map(move |range_bucket| {
+            .map(|range_bucket| {
-                Ok((
+                let bucket_id = range_bucket.bucket.bucket_id;
-                    range_to_string(&range_bucket.range, &field_type)?,
+                let mut agg = range_bucket.bucket.into_intermediate_bucket_entry()?;
-                    range_bucket
+                if let Some(sub_aggregation) = &mut self.sub_agg {
-                        .bucket
+                    sub_aggregation
-                        .into_intermediate_bucket_entry(agg_data)?,
+                        .get_sub_agg_collector()
-                ))
+                        .add_intermediate_aggregation_result(
+                            agg_data,
+                            &mut agg.sub_aggregation_res,
+                            bucket_id,
+                        )?;
+                }
+                Ok((range_to_string(&range_bucket.range, &field_type)?, agg))
             })
             .collect::<crate::Result<_>>()?;
 
@@ -242,73 +276,114 @@ impl SegmentAggregationCollector for SegmentRangeCollector {
     #[inline]
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        self.collect_block(&[doc], agg_data)
-    }
-
-    #[inline]
-    fn collect_block(
-        &mut self,
         docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        // Take request data to avoid borrow conflicts during sub-aggregation
+        let req = agg_data.take_range_req_data(self.accessor_idx);
-        let mut req = agg_data.take_range_req_data(self.accessor_idx);
 
-        req.column_block_accessor.fetch_block(docs, &req.accessor);
+        agg_data
+            .column_block_accessor
+            .fetch_block(docs, &req.accessor);
 
-        for (doc, val) in req
+        let buckets = &mut self.parent_buckets[parent_bucket_id as usize];
+
+        for (doc, val) in agg_data
             .column_block_accessor
             .iter_docid_vals(docs, &req.accessor)
         {
-            let bucket_pos = self.get_bucket_pos(val);
+            let bucket_pos = get_bucket_pos(val, buckets);
-            let bucket = &mut self.buckets[bucket_pos];
+            let bucket = &mut buckets[bucket_pos];
             bucket.bucket.doc_count += 1;
-            if let Some(sub_agg) = bucket.bucket.sub_aggregation.as_mut() {
+            if let Some(sub_agg) = self.sub_agg.as_mut() {
-                sub_agg.collect(doc, agg_data)?;
+                sub_agg.push(bucket.bucket.bucket_id, doc);
             }
         }
 
         agg_data.put_back_range_req_data(self.accessor_idx, req);
+        if let Some(sub_agg) = self.sub_agg.as_mut() {
+            sub_agg.check_flush_local(agg_data)?;
+        }
 
         Ok(())
     }
 
     fn flush(&mut self, agg_data: &mut AggregationsSegmentCtx) -> crate::Result<()> {
-        for bucket in self.buckets.iter_mut() {
+        if let Some(sub_agg) = self.sub_agg.as_mut() {
-            if let Some(sub_agg) = bucket.bucket.sub_aggregation.as_mut() {
+            sub_agg.flush(agg_data)?;
-                sub_agg.flush(agg_data)?;
-            }
         }
         Ok(())
     }
+
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        agg_data: &AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        while self.parent_buckets.len() <= max_bucket as usize {
+            let new_buckets = self.create_new_buckets(agg_data)?;
+            self.parent_buckets.push(new_buckets);
+        }
+
+        Ok(())
+    }
+}
+/// Build a concrete `SegmentRangeCollector` with either a Vec- or HashMap-backed
+/// bucket storage, depending on the column type and aggregation level.
+pub(crate) fn build_segment_range_collector(
+    agg_data: &mut AggregationsSegmentCtx,
+    node: &AggRefNode,
+) -> crate::Result<Box<dyn SegmentAggregationCollector>> {
+    let accessor_idx = node.idx_in_req_data;
+    let req_data = agg_data.get_range_req_data(node.idx_in_req_data);
+    let field_type = req_data.field_type;
+
+    // TODO: A better metric instead of is_top_level would be the number of buckets expected.
+    // E.g. If range agg is not top level, but the parent is a bucket agg with less than 10 buckets,
+    // we can are still in low cardinality territory.
+    let is_low_card = req_data.is_top_level && req_data.req.ranges.len() <= 64;
+
+    let sub_agg = if !node.children.is_empty() {
+        Some(build_segment_agg_collectors(agg_data, &node.children)?)
+    } else {
+        None
+    };
+
+    if is_low_card {
+        Ok(Box::new(SegmentRangeCollector::<LowCardSubAggCache> {
+            sub_agg: sub_agg.map(LowCardCachedSubAggs::new),
+            column_type: field_type,
+            accessor_idx,
+            parent_buckets: Vec::new(),
+            bucket_id_provider: BucketIdProvider::default(),
+            limits: agg_data.context.limits.clone(),
+        }))
+    } else {
+        Ok(Box::new(SegmentRangeCollector::<HighCardSubAggCache> {
+            sub_agg: sub_agg.map(CachedSubAggs::new),
+            column_type: field_type,
+            accessor_idx,
+            parent_buckets: Vec::new(),
+            bucket_id_provider: BucketIdProvider::default(),
+            limits: agg_data.context.limits.clone(),
+        }))
+    }
 }
 
-impl SegmentRangeCollector {
+impl<C: SubAggCache> SegmentRangeCollector<C> {
-    pub(crate) fn from_req_and_validate(
+    pub(crate) fn create_new_buckets(
-        req_data: &mut AggregationsSegmentCtx,
+        &mut self,
-        node: &AggRefNode,
+        agg_data: &AggregationsSegmentCtx,
-    ) -> crate::Result<Self> {
+    ) -> crate::Result<Vec<SegmentRangeAndBucketEntry>> {
-        let accessor_idx = node.idx_in_req_data;
+        let field_type = self.column_type;
-        let (field_type, ranges) = {
+        let req_data = agg_data.get_range_req_data(self.accessor_idx);
-            let req_view = req_data.get_range_req_data(node.idx_in_req_data);
-            (req_view.field_type, req_view.req.ranges.clone())
-        };
-
         // The range input on the request is f64.
         // We need to convert to u64 ranges, because we read the values as u64.
         // The mapping from the conversion is monotonic so ordering is preserved.
-        let sub_agg_prototype = if !node.children.is_empty() {
+        let buckets: Vec<_> = extend_validate_ranges(&req_data.req.ranges, &field_type)?
-            Some(build_segment_agg_collectors(req_data, &node.children)?)
-        } else {
-            None
-        };
-
-        let buckets: Vec<_> = extend_validate_ranges(&ranges, &field_type)?
             .iter()
             .map(|range| {
+                let bucket_id = self.bucket_id_provider.next_bucket_id();
                 let key = range
                     .key
                     .clone()
@@ -317,20 +392,20 @@ impl SegmentRangeCollector {
                 let to = if range.range.end == u64::MAX {
                     None
                 } else {
-                    Some(f64_from_fastfield_u64(range.range.end, &field_type))
+                    Some(f64_from_fastfield_u64(range.range.end, field_type))
                 };
                 let from = if range.range.start == u64::MIN {
                     None
                 } else {
-                    Some(f64_from_fastfield_u64(range.range.start, &field_type))
+                    Some(f64_from_fastfield_u64(range.range.start, field_type))
                 };
-                let sub_aggregation = sub_agg_prototype.clone();
+                // let sub_aggregation = sub_agg_prototype.clone();
 
                 Ok(SegmentRangeAndBucketEntry {
                     range: range.range.clone(),
                     bucket: SegmentRangeBucketEntry {
                         doc_count: 0,
-                        sub_aggregation,
+                        bucket_id,
                         key,
                         from,
                         to,
@@ -339,27 +414,20 @@ impl SegmentRangeCollector {
             })
             .collect::<crate::Result<_>>()?;
 
-        req_data.context.limits.add_memory_consumed(
+        self.limits.add_memory_consumed(
             buckets.len() as u64 * std::mem::size_of::<SegmentRangeAndBucketEntry>() as u64,
         )?;
-
+        Ok(buckets)
-        Ok(SegmentRangeCollector {
-            buckets,
-            column_type: field_type,
-            accessor_idx,
-        })
-    }
-
-    #[inline]
-    fn get_bucket_pos(&self, val: u64) -> usize {
-        let pos = self
-            .buckets
-            .binary_search_by_key(&val, |probe| probe.range.start)
-            .unwrap_or_else(|pos| pos - 1);
-        debug_assert!(self.buckets[pos].range.contains(&val));
-        pos
     }
 }
+#[inline]
+fn get_bucket_pos(val: u64, buckets: &[SegmentRangeAndBucketEntry]) -> usize {
+    let pos = buckets
+        .binary_search_by_key(&val, |probe| probe.range.start)
+        .unwrap_or_else(|pos| pos - 1);
+    debug_assert!(buckets[pos].range.contains(&val));
+    pos
+}
 
 /// Converts the user provided f64 range value to fast field value space.
 ///
@@ -456,7 +524,7 @@ pub(crate) fn range_to_string(
             let val = i64::from_u64(val);
             format_date(val)
         } else {
-            Ok(f64_from_fastfield_u64(val, field_type).to_string())
+            Ok(f64_from_fastfield_u64(val, *field_type).to_string())
         }
     };
 
@@ -486,7 +554,7 @@ mod tests {
     pub fn get_collector_from_ranges(
         ranges: Vec<RangeAggregationRange>,
         field_type: ColumnType,
-    ) -> SegmentRangeCollector {
+    ) -> SegmentRangeCollector<HighCardSubAggCache> {
         let req = RangeAggregation {
             field: "dummy".to_string(),
             ranges,
@@ -506,30 +574,33 @@ mod tests {
                 let to = if range.range.end == u64::MAX {
                     None
                 } else {
-                    Some(f64_from_fastfield_u64(range.range.end, &field_type))
+                    Some(f64_from_fastfield_u64(range.range.end, field_type))
                 };
                 let from = if range.range.start == u64::MIN {
                     None
                 } else {
-                    Some(f64_from_fastfield_u64(range.range.start, &field_type))
+                    Some(f64_from_fastfield_u64(range.range.start, field_type))
                 };
                 SegmentRangeAndBucketEntry {
                     range: range.range.clone(),
                     bucket: SegmentRangeBucketEntry {
                         doc_count: 0,
-                        sub_aggregation: None,
                         key,
                         from,
                         to,
+                        bucket_id: 0,
                     },
                 }
             })
             .collect();
 
         SegmentRangeCollector {
-            buckets,
+            parent_buckets: vec![buckets],
             column_type: field_type,
             accessor_idx: 0,
+            sub_agg: None,
+            bucket_id_provider: Default::default(),
+            limits: AggregationLimitsGuard::default(),
         }
     }
 
@@ -776,7 +847,7 @@ mod tests {
         let buckets = vec![(10f64..20f64).into(), (30f64..40f64).into()];
         let collector = get_collector_from_ranges(buckets, ColumnType::F64);
 
-        let buckets = collector.buckets;
+        let buckets = collector.parent_buckets[0].clone();
         assert_eq!(buckets[0].range.start, u64::MIN);
         assert_eq!(buckets[0].range.end, 10f64.to_u64());
         assert_eq!(buckets[1].range.start, 10f64.to_u64());
@@ -799,7 +870,7 @@ mod tests {
         ];
         let collector = get_collector_from_ranges(buckets, ColumnType::F64);
 
-        let buckets = collector.buckets;
+        let buckets = collector.parent_buckets[0].clone();
         assert_eq!(buckets[0].range.start, u64::MIN);
         assert_eq!(buckets[0].range.end, 10f64.to_u64());
         assert_eq!(buckets[1].range.start, 10f64.to_u64());
@@ -814,7 +885,7 @@ mod tests {
         let buckets = vec![(-10f64..-1f64).into()];
         let collector = get_collector_from_ranges(buckets, ColumnType::F64);
 
-        let buckets = collector.buckets;
+        let buckets = collector.parent_buckets[0].clone();
         assert_eq!(&buckets[0].bucket.key.to_string(), "*--10");
         assert_eq!(&buckets[buckets.len() - 1].bucket.key.to_string(), "-1-*");
     }
@@ -823,7 +894,7 @@ mod tests {
         let buckets = vec![(0f64..10f64).into()];
         let collector = get_collector_from_ranges(buckets, ColumnType::F64);
 
-        let buckets = collector.buckets;
+        let buckets = collector.parent_buckets[0].clone();
         assert_eq!(&buckets[0].bucket.key.to_string(), "*-0");
         assert_eq!(&buckets[buckets.len() - 1].bucket.key.to_string(), "10-*");
     }
@@ -832,7 +903,7 @@ mod tests {
     fn range_binary_search_test_u64() {
         let check_ranges = |ranges: Vec<RangeAggregationRange>| {
             let collector = get_collector_from_ranges(ranges, ColumnType::U64);
-            let search = |val: u64| collector.get_bucket_pos(val);
+            let search = |val: u64| get_bucket_pos(val, &collector.parent_buckets[0]);
 
             assert_eq!(search(u64::MIN), 0);
             assert_eq!(search(9), 0);
@@ -878,7 +949,7 @@ mod tests {
         let ranges = vec![(10.0..100.0).into()];
 
         let collector = get_collector_from_ranges(ranges, ColumnType::F64);
-        let search = |val: u64| collector.get_bucket_pos(val);
+        let search = |val: u64| get_bucket_pos(val, &collector.parent_buckets[0]);
 
         assert_eq!(search(u64::MIN), 0);
         assert_eq!(search(9f64.to_u64()), 0);
@@ -890,63 +961,3 @@ mod tests {
                                              // the max value
     }
 }
-
-#[cfg(all(test, feature = "unstable"))]
-mod bench {
-
-    use itertools::Itertools;
-    use rand::seq::SliceRandom;
-    use rand::thread_rng;
-
-    use super::*;
-    use crate::aggregation::bucket::range::tests::get_collector_from_ranges;
-
-    const TOTAL_DOCS: u64 = 1_000_000u64;
-    const NUM_DOCS: u64 = 50_000u64;
-
-    fn get_collector_with_buckets(num_buckets: u64, num_docs: u64) -> SegmentRangeCollector {
-        let bucket_size = num_docs / num_buckets;
-        let mut buckets: Vec<RangeAggregationRange> = vec![];
-        for i in 0..num_buckets {
-            let bucket_start = (i * bucket_size) as f64;
-            buckets.push((bucket_start..bucket_start + bucket_size as f64).into())
-        }
-
-        get_collector_from_ranges(buckets, ColumnType::U64)
-    }
-
-    fn get_rand_docs(total_docs: u64, num_docs_returned: u64) -> Vec<u64> {
-        let mut rng = thread_rng();
-
-        let all_docs = (0..total_docs - 1).collect_vec();
-        let mut vals = all_docs
-            .as_slice()
-            .choose_multiple(&mut rng, num_docs_returned as usize)
-            .cloned()
-            .collect_vec();
-        vals.sort();
-        vals
-    }
-
-    fn bench_range_binary_search(b: &mut test::Bencher, num_buckets: u64) {
-        let collector = get_collector_with_buckets(num_buckets, TOTAL_DOCS);
-        let vals = get_rand_docs(TOTAL_DOCS, NUM_DOCS);
-        b.iter(|| {
-            let mut bucket_pos = 0;
-            for val in &vals {
-                bucket_pos = collector.get_bucket_pos(*val);
-            }
-            bucket_pos
-        })
-    }
-
-    #[bench]
-    fn bench_range_100_buckets(b: &mut test::Bencher) {
-        bench_range_binary_search(b, 100)
-    }
-
-    #[bench]
-    fn bench_range_10_buckets(b: &mut test::Bencher) {
-        bench_range_binary_search(b, 10)
-    }
-}

src/aggregation/bucket/term_missing_agg.rs

@@ -5,11 +5,13 @@ use crate::aggregation::agg_data::{
     build_segment_agg_collectors, AggRefNode, AggregationsSegmentCtx,
 };
 use crate::aggregation::bucket::term_agg::TermsAggregation;
+use crate::aggregation::cached_sub_aggs::{CachedSubAggs, HighCardCachedSubAggs};
 use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateAggregationResults, IntermediateBucketResult,
     IntermediateKey, IntermediateTermBucketEntry, IntermediateTermBucketResult,
 };
-use crate::aggregation::segment_agg_result::SegmentAggregationCollector;
+use crate::aggregation::segment_agg_result::{BucketIdProvider, SegmentAggregationCollector};
+use crate::aggregation::BucketId;
 
 /// Special aggregation to handle missing values for term aggregations.
 /// This missing aggregation will check multiple columns for existence.
@@ -35,41 +37,55 @@ impl MissingTermAggReqData {
     }
 }
 
-/// The specialized missing term aggregation.
 #[derive(Default, Debug, Clone)]
-pub struct TermMissingAgg {
+struct MissingCount {
     missing_count: u32,
+    bucket_id: BucketId,
+}
+
+/// The specialized missing term aggregation.
+#[derive(Default, Debug)]
+pub struct TermMissingAgg {
     accessor_idx: usize,
-    sub_agg: Option<Box<dyn SegmentAggregationCollector>>,
+    sub_agg: Option<HighCardCachedSubAggs>,
+    /// Idx = parent bucket id, Value = missing count for that bucket
+    missing_count_per_bucket: Vec<MissingCount>,
+    bucket_id_provider: BucketIdProvider,
 }
 impl TermMissingAgg {
     pub(crate) fn new(
-        req_data: &mut AggregationsSegmentCtx,
+        agg_data: &mut AggregationsSegmentCtx,
         node: &AggRefNode,
     ) -> crate::Result<Self> {
         let has_sub_aggregations = !node.children.is_empty();
         let accessor_idx = node.idx_in_req_data;
         let sub_agg = if has_sub_aggregations {
-            let sub_aggregation = build_segment_agg_collectors(req_data, &node.children)?;
+            let sub_aggregation = build_segment_agg_collectors(agg_data, &node.children)?;
             Some(sub_aggregation)
         } else {
             None
         };
 
+        let sub_agg = sub_agg.map(CachedSubAggs::new);
+        let bucket_id_provider = BucketIdProvider::default();
+
         Ok(Self {
             accessor_idx,
             sub_agg,
-            ..Default::default()
+            missing_count_per_bucket: Vec::new(),
+            bucket_id_provider,
         })
     }
 }
 
 impl SegmentAggregationCollector for TermMissingAgg {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
+        self.prepare_max_bucket(parent_bucket_id, agg_data)?;
         let req_data = agg_data.get_missing_term_req_data(self.accessor_idx);
         let term_agg = &req_data.req;
         let missing = term_agg
@@ -80,13 +96,16 @@ impl SegmentAggregationCollector for TermMissingAgg {
         let mut entries: FxHashMap<IntermediateKey, IntermediateTermBucketEntry> =
             Default::default();
 
+        let missing_count = &self.missing_count_per_bucket[parent_bucket_id as usize];
         let mut missing_entry = IntermediateTermBucketEntry {
-            doc_count: self.missing_count,
+            doc_count: missing_count.missing_count,
             sub_aggregation: Default::default(),
         };
-        if let Some(sub_agg) = self.sub_agg {
+        if let Some(sub_agg) = &mut self.sub_agg {
             let mut res = IntermediateAggregationResults::default();
-            sub_agg.add_intermediate_aggregation_result(agg_data, &mut res)?;
+            sub_agg
+                .get_sub_agg_collector()
+                .add_intermediate_aggregation_result(agg_data, &mut res, missing_count.bucket_id)?;
             missing_entry.sub_aggregation = res;
         }
         entries.insert(missing.into(), missing_entry);
@@ -109,30 +128,52 @@ impl SegmentAggregationCollector for TermMissingAgg {
 
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
+        docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
+        let bucket = &mut self.missing_count_per_bucket[parent_bucket_id as usize];
         let req_data = agg_data.get_missing_term_req_data(self.accessor_idx);
-        let has_value = req_data
+
-            .accessors
+        for doc in docs {
-            .iter()
+            let doc = *doc;
-            .any(|(acc, _)| acc.index.has_value(doc));
+            let has_value = req_data
-        if !has_value {
+                .accessors
-            self.missing_count += 1;
+                .iter()
-            if let Some(sub_agg) = self.sub_agg.as_mut() {
+                .any(|(acc, _)| acc.index.has_value(doc));
-                sub_agg.collect(doc, agg_data)?;
+            if !has_value {
+                bucket.missing_count += 1;
+
+                if let Some(sub_agg) = self.sub_agg.as_mut() {
+                    sub_agg.push(bucket.bucket_id, doc);
+                }
             }
         }
+
+        if let Some(sub_agg) = self.sub_agg.as_mut() {
+            sub_agg.check_flush_local(agg_data)?;
+        }
         Ok(())
     }
 
-    fn collect_block(
+    fn prepare_max_bucket(
         &mut self,
-        docs: &[crate::DocId],
+        max_bucket: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
+        _agg_data: &AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        for doc in docs {
+        while self.missing_count_per_bucket.len() <= max_bucket as usize {
-            self.collect(*doc, agg_data)?;
+            let bucket_id = self.bucket_id_provider.next_bucket_id();
+            self.missing_count_per_bucket.push(MissingCount {
+                missing_count: 0,
+                bucket_id,
+            });
+        }
+        Ok(())
+    }
+
+    fn flush(&mut self, agg_data: &mut AggregationsSegmentCtx) -> crate::Result<()> {
+        if let Some(sub_agg) = self.sub_agg.as_mut() {
+            sub_agg.flush(agg_data)?;
         }
         Ok(())
     }

src/aggregation/buf_collector.rs

@@ -1,87 +0,0 @@
-use super::intermediate_agg_result::IntermediateAggregationResults;
-use super::segment_agg_result::SegmentAggregationCollector;
-use crate::aggregation::agg_data::AggregationsSegmentCtx;
-use crate::DocId;
-
-#[cfg(test)]
-pub(crate) const DOC_BLOCK_SIZE: usize = 64;
-
-#[cfg(not(test))]
-pub(crate) const DOC_BLOCK_SIZE: usize = 256;
-
-pub(crate) type DocBlock = [DocId; DOC_BLOCK_SIZE];
-
-/// BufAggregationCollector buffers documents before calling collect_block().
-#[derive(Clone)]
-pub(crate) struct BufAggregationCollector {
-    pub(crate) collector: Box<dyn SegmentAggregationCollector>,
-    staged_docs: DocBlock,
-    num_staged_docs: usize,
-}
-
-impl std::fmt::Debug for BufAggregationCollector {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        f.debug_struct("SegmentAggregationResultsCollector")
-            .field("staged_docs", &&self.staged_docs[..self.num_staged_docs])
-            .field("num_staged_docs", &self.num_staged_docs)
-            .finish()
-    }
-}
-
-impl BufAggregationCollector {
-    pub fn new(collector: Box<dyn SegmentAggregationCollector>) -> Self {
-        Self {
-            collector,
-            num_staged_docs: 0,
-            staged_docs: [0; DOC_BLOCK_SIZE],
-        }
-    }
-}
-
-impl SegmentAggregationCollector for BufAggregationCollector {
-    #[inline]
-    fn add_intermediate_aggregation_result(
-        self: Box<Self>,
-        agg_data: &AggregationsSegmentCtx,
-        results: &mut IntermediateAggregationResults,
-    ) -> crate::Result<()> {
-        Box::new(self.collector).add_intermediate_aggregation_result(agg_data, results)
-    }
-
-    #[inline]
-    fn collect(
-        &mut self,
-        doc: crate::DocId,
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        self.staged_docs[self.num_staged_docs] = doc;
-        self.num_staged_docs += 1;
-        if self.num_staged_docs == self.staged_docs.len() {
-            self.collector
-                .collect_block(&self.staged_docs[..self.num_staged_docs], agg_data)?;
-            self.num_staged_docs = 0;
-        }
-        Ok(())
-    }
-
-    #[inline]
-    fn collect_block(
-        &mut self,
-        docs: &[crate::DocId],
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        self.collector.collect_block(docs, agg_data)?;
-        Ok(())
-    }
-
-    #[inline]
-    fn flush(&mut self, agg_data: &mut AggregationsSegmentCtx) -> crate::Result<()> {
-        self.collector
-            .collect_block(&self.staged_docs[..self.num_staged_docs], agg_data)?;
-        self.num_staged_docs = 0;
-
-        self.collector.flush(agg_data)?;
-
-        Ok(())
-    }
-}

src/aggregation/cached_sub_aggs.rs

@@ -0,0 +1,245 @@
+use std::fmt::Debug;
+
+use super::segment_agg_result::SegmentAggregationCollector;
+use crate::aggregation::agg_data::AggregationsSegmentCtx;
+use crate::aggregation::bucket::MAX_NUM_TERMS_FOR_VEC;
+use crate::aggregation::BucketId;
+use crate::DocId;
+
+/// A cache for sub-aggregations, storing doc ids per bucket id.
+/// Depending on the cardinality of the parent aggregation, we use different
+/// storage strategies.
+///
+/// ## Low Cardinality
+/// Cardinality here refers to the number of unique flattened buckets that can be created
+/// by the parent aggregation.
+/// Flattened buckets are the result of combining all buckets per collector
+/// into a single list of buckets, where each bucket is identified by its BucketId.
+///
+/// ## Usage
+/// Since this is caching for sub-aggregations, it is only used by bucket
+/// aggregations.
+///
+/// TODO: consider using a more advanced data structure for high cardinality
+/// aggregations.
+/// What this datastructure does in general is to group docs by bucket id.
+#[derive(Debug)]
+pub(crate) struct CachedSubAggs<C: SubAggCache> {
+    cache: C,
+    sub_agg_collector: Box<dyn SegmentAggregationCollector>,
+    num_docs: usize,
+}
+
+pub type LowCardCachedSubAggs = CachedSubAggs<LowCardSubAggCache>;
+pub type HighCardCachedSubAggs = CachedSubAggs<HighCardSubAggCache>;
+
+const FLUSH_THRESHOLD: usize = 2048;
+
+/// A trait for caching sub-aggregation doc ids per bucket id.
+/// Different implementations can be used depending on the cardinality
+/// of the parent aggregation.
+pub trait SubAggCache: Debug {
+    fn new() -> Self;
+    fn push(&mut self, bucket_id: BucketId, doc_id: DocId);
+    fn flush_local(
+        &mut self,
+        sub_agg: &mut Box<dyn SegmentAggregationCollector>,
+        agg_data: &mut AggregationsSegmentCtx,
+        force: bool,
+    ) -> crate::Result<()>;
+}
+
+impl<Backend: SubAggCache + Debug> CachedSubAggs<Backend> {
+    pub fn new(sub_agg: Box<dyn SegmentAggregationCollector>) -> Self {
+        Self {
+            cache: Backend::new(),
+            sub_agg_collector: sub_agg,
+            num_docs: 0,
+        }
+    }
+
+    pub fn get_sub_agg_collector(&mut self) -> &mut Box<dyn SegmentAggregationCollector> {
+        &mut self.sub_agg_collector
+    }
+
+    #[inline]
+    pub fn push(&mut self, bucket_id: BucketId, doc_id: DocId) {
+        self.cache.push(bucket_id, doc_id);
+        self.num_docs += 1;
+    }
+
+    /// Check if we need to flush based on the number of documents cached.
+    /// If so, flushes the cache to the provided aggregation collector.
+    pub fn check_flush_local(
+        &mut self,
+        agg_data: &mut AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        if self.num_docs >= FLUSH_THRESHOLD {
+            self.cache
+                .flush_local(&mut self.sub_agg_collector, agg_data, false)?;
+            self.num_docs = 0;
+        }
+        Ok(())
+    }
+
+    /// Note: this _does_ flush the sub aggregations.
+    pub fn flush(&mut self, agg_data: &mut AggregationsSegmentCtx) -> crate::Result<()> {
+        if self.num_docs != 0 {
+            self.cache
+                .flush_local(&mut self.sub_agg_collector, agg_data, true)?;
+            self.num_docs = 0;
+        }
+        self.sub_agg_collector.flush(agg_data)?;
+        Ok(())
+    }
+}
+
+/// Number of partitions for high cardinality sub-aggregation cache.
+const NUM_PARTITIONS: usize = 16;
+
+#[derive(Debug)]
+pub(crate) struct HighCardSubAggCache {
+    /// This weird partitioning is used to do some cheap grouping on the bucket ids.
+    /// bucket ids are dense, e.g. when we don't detect the cardinality as low cardinality,
+    /// but there are just 16 bucket ids, each bucket id will go to its own partition.
+    ///
+    /// We want to keep this cheap, because high cardinality aggregations can have a lot of
+    /// buckets, and there may be nothing to group.
+    partitions: Box<[PartitionEntry; NUM_PARTITIONS]>,
+}
+
+impl HighCardSubAggCache {
+    #[inline]
+    fn clear(&mut self) {
+        for partition in self.partitions.iter_mut() {
+            partition.clear();
+        }
+    }
+}
+
+#[derive(Debug, Clone, Default)]
+struct PartitionEntry {
+    bucket_ids: Vec<BucketId>,
+    docs: Vec<DocId>,
+}
+
+impl PartitionEntry {
+    #[inline]
+    fn clear(&mut self) {
+        self.bucket_ids.clear();
+        self.docs.clear();
+    }
+}
+
+impl SubAggCache for HighCardSubAggCache {
+    fn new() -> Self {
+        Self {
+            partitions: Box::new(core::array::from_fn(|_| PartitionEntry::default())),
+        }
+    }
+
+    fn push(&mut self, bucket_id: BucketId, doc_id: DocId) {
+        let idx = bucket_id % NUM_PARTITIONS as u32;
+        let slot = &mut self.partitions[idx as usize];
+        slot.bucket_ids.push(bucket_id);
+        slot.docs.push(doc_id);
+    }
+
+    fn flush_local(
+        &mut self,
+        sub_agg: &mut Box<dyn SegmentAggregationCollector>,
+        agg_data: &mut AggregationsSegmentCtx,
+        _force: bool,
+    ) -> crate::Result<()> {
+        let mut max_bucket = 0u32;
+        for partition in self.partitions.iter() {
+            if let Some(&local_max) = partition.bucket_ids.iter().max() {
+                max_bucket = max_bucket.max(local_max);
+            }
+        }
+
+        sub_agg.prepare_max_bucket(max_bucket, agg_data)?;
+
+        for slot in self.partitions.iter() {
+            if !slot.bucket_ids.is_empty() {
+                // Reduce dynamic dispatch overhead by collecting a full partition in one call.
+                sub_agg.collect_multiple(&slot.bucket_ids, &slot.docs, agg_data)?;
+            }
+        }
+
+        self.clear();
+        Ok(())
+    }
+}
+
+#[derive(Debug)]
+pub(crate) struct LowCardSubAggCache {
+    /// Cache doc ids per bucket for sub-aggregations.
+    ///
+    /// The outer Vec is indexed by BucketId.
+    per_bucket_docs: Vec<Vec<DocId>>,
+}
+
+impl LowCardSubAggCache {
+    #[inline]
+    fn clear(&mut self) {
+        for v in &mut self.per_bucket_docs {
+            v.clear();
+        }
+    }
+}
+
+impl SubAggCache for LowCardSubAggCache {
+    fn new() -> Self {
+        Self {
+            per_bucket_docs: Vec::new(),
+        }
+    }
+
+    fn push(&mut self, bucket_id: BucketId, doc_id: DocId) {
+        let idx = bucket_id as usize;
+        if self.per_bucket_docs.len() <= idx {
+            self.per_bucket_docs.resize_with(idx + 1, Vec::new);
+        }
+        self.per_bucket_docs[idx].push(doc_id);
+    }
+
+    fn flush_local(
+        &mut self,
+        sub_agg: &mut Box<dyn SegmentAggregationCollector>,
+        agg_data: &mut AggregationsSegmentCtx,
+        force: bool,
+    ) -> crate::Result<()> {
+        // Pre-aggregated: call collect per bucket.
+        let max_bucket = (self.per_bucket_docs.len() as BucketId).saturating_sub(1);
+        sub_agg.prepare_max_bucket(max_bucket, agg_data)?;
+        // The threshold above which we flush buckets individually.
+        // Note: We need to make sure that we don't lock ourselves into a situation where we hit
+        // the FLUSH_THRESHOLD, but never flush any buckets. (except the final flush)
+        let mut bucket_treshold = FLUSH_THRESHOLD / (self.per_bucket_docs.len().max(1) * 2);
+        const _: () = {
+            // MAX_NUM_TERMS_FOR_VEC threshold is used for term aggregations
+            // Note: There may be other flexible values, for other aggregations, but we can use the
+            // const value here as a upper bound. (better than nothing)
+            let bucket_treshold_limit = FLUSH_THRESHOLD / (MAX_NUM_TERMS_FOR_VEC as usize * 2);
+            assert!(
+                bucket_treshold_limit > 0,
+                "Bucket threshold must be greater than 0"
+            );
+        };
+        if force {
+            bucket_treshold = 0;
+        }
+        for (bucket_id, docs) in self
+            .per_bucket_docs
+            .iter()
+            .enumerate()
+            .filter(|(_, docs)| docs.len() > bucket_treshold)
+        {
+            sub_agg.collect(bucket_id as BucketId, docs, agg_data)?;
+        }
+
+        self.clear();
+        Ok(())
+    }
+}

src/aggregation/collector.rs

@@ -1,9 +1,9 @@
 use super::agg_req::Aggregations;
 use super::agg_result::AggregationResults;
-use super::buf_collector::BufAggregationCollector;
+use super::cached_sub_aggs::LowCardCachedSubAggs;
 use super::intermediate_agg_result::IntermediateAggregationResults;
-use super::segment_agg_result::SegmentAggregationCollector;
 use super::AggContextParams;
+// group buffering strategy is chosen explicitly by callers; no need to hash-group on the fly.
 use crate::aggregation::agg_data::{
     build_aggregations_data_from_req, build_segment_agg_collectors_root, AggregationsSegmentCtx,
 };
@@ -136,7 +136,7 @@ fn merge_fruits(
 /// `AggregationSegmentCollector` does the aggregation collection on a segment.
 pub struct AggregationSegmentCollector {
     aggs_with_accessor: AggregationsSegmentCtx,
-    agg_collector: BufAggregationCollector,
+    agg_collector: LowCardCachedSubAggs,
     error: Option<TantivyError>,
 }
 
@@ -151,8 +151,11 @@ impl AggregationSegmentCollector {
     ) -> crate::Result<Self> {
         let mut agg_data =
             build_aggregations_data_from_req(agg, reader, segment_ordinal, context.clone())?;
-        let result =
+        let mut result =
-            BufAggregationCollector::new(build_segment_agg_collectors_root(&mut agg_data)?);
+            LowCardCachedSubAggs::new(build_segment_agg_collectors_root(&mut agg_data)?);
+        result
+            .get_sub_agg_collector()
+            .prepare_max_bucket(0, &agg_data)?; // prepare for bucket zero
 
         Ok(AggregationSegmentCollector {
             aggs_with_accessor: agg_data,
@@ -170,26 +173,31 @@ impl SegmentCollector for AggregationSegmentCollector {
         if self.error.is_some() {
             return;
         }
-        if let Err(err) = self
+        self.agg_collector.push(0, doc);
+        match self
             .agg_collector
-            .collect(doc, &mut self.aggs_with_accessor)
+            .check_flush_local(&mut self.aggs_with_accessor)
         {
-            self.error = Some(err);
+            Ok(_) => {}
+            Err(e) => {
+                self.error = Some(e);
+            }
         }
     }
-
-    /// The query pushes the documents to the collector via this method.
-    ///
-    /// Only valid for Collectors that ignore docs
     fn collect_block(&mut self, docs: &[DocId]) {
         if self.error.is_some() {
             return;
         }
-        if let Err(err) = self
+
-            .agg_collector
+        match self.agg_collector.get_sub_agg_collector().collect(
-            .collect_block(docs, &mut self.aggs_with_accessor)
+            0,
-        {
+            docs,
-            self.error = Some(err);
+            &mut self.aggs_with_accessor,
+        ) {
+            Ok(_) => {}
+            Err(e) => {
+                self.error = Some(e);
+            }
         }
     }
 
@@ -200,10 +208,13 @@ impl SegmentCollector for AggregationSegmentCollector {
         self.agg_collector.flush(&mut self.aggs_with_accessor)?;
 
         let mut sub_aggregation_res = IntermediateAggregationResults::default();
-        Box::new(self.agg_collector).add_intermediate_aggregation_result(
+        self.agg_collector
-            &self.aggs_with_accessor,
+            .get_sub_agg_collector()
-            &mut sub_aggregation_res,
+            .add_intermediate_aggregation_result(
-        )?;
+                &self.aggs_with_accessor,
+                &mut sub_aggregation_res,
+                0,
+            )?;
 
         Ok(sub_aggregation_res)
     }

src/aggregation/intermediate_agg_result.rs

@@ -792,7 +792,7 @@ pub struct IntermediateRangeBucketEntry {
     /// The number of documents in the bucket.
     pub doc_count: u64,
     /// The sub_aggregation in this bucket.
-    pub sub_aggregation: IntermediateAggregationResults,
+    pub sub_aggregation_res: IntermediateAggregationResults,
     /// The from range of the bucket. Equals `f64::MIN` when `None`.
     pub from: Option<f64>,
     /// The to range of the bucket. Equals `f64::MAX` when `None`.
@@ -811,7 +811,7 @@ impl IntermediateRangeBucketEntry {
             key: self.key.into(),
             doc_count: self.doc_count,
             sub_aggregation: self
-                .sub_aggregation
+                .sub_aggregation_res
                 .into_final_result_internal(req, limits)?,
             to: self.to,
             from: self.from,
@@ -857,7 +857,8 @@ impl MergeFruits for IntermediateTermBucketEntry {
 impl MergeFruits for IntermediateRangeBucketEntry {
     fn merge_fruits(&mut self, other: IntermediateRangeBucketEntry) -> crate::Result<()> {
         self.doc_count += other.doc_count;
-        self.sub_aggregation.merge_fruits(other.sub_aggregation)?;
+        self.sub_aggregation_res
+            .merge_fruits(other.sub_aggregation_res)?;
         Ok(())
     }
 }
@@ -887,7 +888,7 @@ mod tests {
                 IntermediateRangeBucketEntry {
                     key: IntermediateKey::Str(key.to_string()),
                     doc_count: *doc_count,
-                    sub_aggregation: Default::default(),
+                    sub_aggregation_res: Default::default(),
                     from: None,
                     to: None,
                 },
@@ -920,7 +921,7 @@ mod tests {
                     doc_count: *doc_count,
                     from: None,
                     to: None,
-                    sub_aggregation: get_sub_test_tree(&[(
+                    sub_aggregation_res: get_sub_test_tree(&[(
                         sub_aggregation_key.to_string(),
                         *sub_aggregation_count,
                     )]),

src/aggregation/metric/average.rs

@@ -52,10 +52,8 @@ pub struct IntermediateAverage {
 
 impl IntermediateAverage {
     /// Creates a new [`IntermediateAverage`] instance from a [`SegmentStatsCollector`].
-    pub(crate) fn from_collector(collector: SegmentStatsCollector) -> Self {
+    pub(crate) fn from_stats(stats: IntermediateStats) -> Self {
-        Self {
+        Self { stats }
-            stats: collector.stats,
-        }
     }
     /// Merges the other intermediate result into self.
     pub fn merge_fruits(&mut self, other: IntermediateAverage) {

src/aggregation/metric/cardinality.rs

@@ -2,7 +2,7 @@ use std::collections::hash_map::DefaultHasher;
 use std::hash::{BuildHasher, Hasher};
 
 use columnar::column_values::CompactSpaceU64Accessor;
-use columnar::{Column, ColumnBlockAccessor, ColumnType, Dictionary, StrColumn};
+use columnar::{Column, ColumnType, Dictionary, StrColumn};
 use common::f64_to_u64;
 use hyperloglogplus::{HyperLogLog, HyperLogLogPlus};
 use rustc_hash::FxHashSet;
@@ -106,8 +106,6 @@ pub struct CardinalityAggReqData {
     pub str_dict_column: Option<StrColumn>,
     /// The missing value normalized to the internal u64 representation of the field type.
     pub missing_value_for_accessor: Option<u64>,
-    /// The column block accessor to access the fast field values.
-    pub(crate) column_block_accessor: ColumnBlockAccessor<u64>,
     /// The name of the aggregation.
     pub name: String,
     /// The aggregation request.
@@ -135,45 +133,34 @@ impl CardinalityAggregationReq {
     }
 }
 
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Debug)]
 pub(crate) struct SegmentCardinalityCollector {
-    cardinality: CardinalityCollector,
+    buckets: Vec<SegmentCardinalityCollectorBucket>,
-    entries: FxHashSet<u64>,
     accessor_idx: usize,
+    /// The column accessor to access the fast field values.
+    accessor: Column<u64>,
+    /// The column_type of the field.
+    column_type: ColumnType,
+    /// The missing value normalized to the internal u64 representation of the field type.
+    missing_value_for_accessor: Option<u64>,
 }
 
-impl SegmentCardinalityCollector {
+#[derive(Clone, Debug, PartialEq, Default)]
-    pub fn from_req(column_type: ColumnType, accessor_idx: usize) -> Self {
+pub(crate) struct SegmentCardinalityCollectorBucket {
+    cardinality: CardinalityCollector,
+    entries: FxHashSet<u64>,
+}
+impl SegmentCardinalityCollectorBucket {
+    pub fn new(column_type: ColumnType) -> Self {
         Self {
             cardinality: CardinalityCollector::new(column_type as u8),
-            entries: Default::default(),
+            entries: FxHashSet::default(),
-            accessor_idx,
         }
     }
-
-    fn fetch_block_with_field(
-        &mut self,
-        docs: &[crate::DocId],
-        agg_data: &mut CardinalityAggReqData,
-    ) {
-        if let Some(missing) = agg_data.missing_value_for_accessor {
-            agg_data.column_block_accessor.fetch_block_with_missing(
-                docs,
-                &agg_data.accessor,
-                missing,
-            );
-        } else {
-            agg_data
-                .column_block_accessor
-                .fetch_block(docs, &agg_data.accessor);
-        }
-    }
-
     fn into_intermediate_metric_result(
         mut self,
-        agg_data: &AggregationsSegmentCtx,
+        req_data: &CardinalityAggReqData,
     ) -> crate::Result<IntermediateMetricResult> {
-        let req_data = &agg_data.get_cardinality_req_data(self.accessor_idx);
         if req_data.column_type == ColumnType::Str {
             let fallback_dict = Dictionary::empty();
             let dict = req_data
@@ -194,6 +181,7 @@ impl SegmentCardinalityCollector {
                     term_ids.push(term_ord as u32);
                 }
             }
+
             term_ids.sort_unstable();
             dict.sorted_ords_to_term_cb(term_ids.iter().map(|term| *term as u64), |term| {
                 self.cardinality.sketch.insert_any(&term);
@@ -227,16 +215,49 @@ impl SegmentCardinalityCollector {
     }
 }
 
+impl SegmentCardinalityCollector {
+    pub fn from_req(
+        column_type: ColumnType,
+        accessor_idx: usize,
+        accessor: Column<u64>,
+        missing_value_for_accessor: Option<u64>,
+    ) -> Self {
+        Self {
+            buckets: vec![SegmentCardinalityCollectorBucket::new(column_type); 1],
+            column_type,
+            accessor_idx,
+            accessor,
+            missing_value_for_accessor,
+        }
+    }
+
+    fn fetch_block_with_field(
+        &mut self,
+        docs: &[crate::DocId],
+        agg_data: &mut AggregationsSegmentCtx,
+    ) {
+        agg_data.column_block_accessor.fetch_block_with_missing(
+            docs,
+            &self.accessor,
+            self.missing_value_for_accessor,
+        );
+    }
+}
+
 impl SegmentAggregationCollector for SegmentCardinalityCollector {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
+        self.prepare_max_bucket(parent_bucket_id, agg_data)?;
         let req_data = &agg_data.get_cardinality_req_data(self.accessor_idx);
         let name = req_data.name.to_string();
+        // take the bucket in buckets and replace it with a new empty one
+        let bucket = std::mem::take(&mut self.buckets[parent_bucket_id as usize]);
 
-        let intermediate_result = self.into_intermediate_metric_result(agg_data)?;
+        let intermediate_result = bucket.into_intermediate_metric_result(req_data)?;
         results.push(
             name,
             IntermediateAggregationResult::Metric(intermediate_result),
@@ -247,27 +268,20 @@ impl SegmentAggregationCollector for SegmentCardinalityCollector {
 
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        self.collect_block(&[doc], agg_data)
-    }
-
-    fn collect_block(
-        &mut self,
         docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        let req_data = agg_data.get_cardinality_req_data_mut(self.accessor_idx);
+        self.fetch_block_with_field(docs, agg_data);
-        self.fetch_block_with_field(docs, req_data);
+        let bucket = &mut self.buckets[parent_bucket_id as usize];
 
-        let col_block_accessor = &req_data.column_block_accessor;
+        let col_block_accessor = &agg_data.column_block_accessor;
-        if req_data.column_type == ColumnType::Str {
+        if self.column_type == ColumnType::Str {
             for term_ord in col_block_accessor.iter_vals() {
-                self.entries.insert(term_ord);
+                bucket.entries.insert(term_ord);
             }
-        } else if req_data.column_type == ColumnType::IpAddr {
+        } else if self.column_type == ColumnType::IpAddr {
-            let compact_space_accessor = req_data
+            let compact_space_accessor = self
                 .accessor
                 .values
                 .clone()
@@ -282,16 +296,29 @@ impl SegmentAggregationCollector for SegmentCardinalityCollector {
                 })?;
             for val in col_block_accessor.iter_vals() {
                 let val: u128 = compact_space_accessor.compact_to_u128(val as u32);
-                self.cardinality.sketch.insert_any(&val);
+                bucket.cardinality.sketch.insert_any(&val);
             }
         } else {
             for val in col_block_accessor.iter_vals() {
-                self.cardinality.sketch.insert_any(&val);
+                bucket.cardinality.sketch.insert_any(&val);
             }
         }
 
         Ok(())
     }
+
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        _agg_data: &AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        if max_bucket as usize >= self.buckets.len() {
+            self.buckets.resize_with(max_bucket as usize + 1, || {
+                SegmentCardinalityCollectorBucket::new(self.column_type)
+            });
+        }
+        Ok(())
+    }
 }
 
 #[derive(Clone, Debug, Serialize, Deserialize)]

src/aggregation/metric/count.rs

@@ -52,10 +52,8 @@ pub struct IntermediateCount {
 
 impl IntermediateCount {
     /// Creates a new [`IntermediateCount`] instance from a [`SegmentStatsCollector`].
-    pub(crate) fn from_collector(collector: SegmentStatsCollector) -> Self {
+    pub(crate) fn from_stats(stats: IntermediateStats) -> Self {
-        Self {
+        Self { stats }
-            stats: collector.stats,
-        }
     }
     /// Merges the other intermediate result into self.
     pub fn merge_fruits(&mut self, other: IntermediateCount) {

src/aggregation/metric/extended_stats.rs

@@ -8,10 +8,9 @@ use crate::aggregation::agg_data::AggregationsSegmentCtx;
 use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateAggregationResults, IntermediateMetricResult,
 };
-use crate::aggregation::metric::MetricAggReqData;
 use crate::aggregation::segment_agg_result::SegmentAggregationCollector;
 use crate::aggregation::*;
-use crate::{DocId, TantivyError};
+use crate::TantivyError;
 
 /// A multi-value metric aggregation that computes a collection of extended statistics
 /// on numeric values that are extracted
@@ -318,51 +317,28 @@ impl IntermediateExtendedStats {
     }
 }
 
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Debug)]
 pub(crate) struct SegmentExtendedStatsCollector {
+    name: String,
     missing: Option<u64>,
     field_type: ColumnType,
-    pub(crate) extended_stats: IntermediateExtendedStats,
+    accessor: columnar::Column<u64>,
-    pub(crate) accessor_idx: usize,
+    buckets: Vec<IntermediateExtendedStats>,
-    val_cache: Vec<u64>,
+    sigma: Option<f64>,
 }
 
 impl SegmentExtendedStatsCollector {
-    pub fn from_req(
+    pub fn from_req(req: &MetricAggReqData, sigma: Option<f64>) -> Self {
-        field_type: ColumnType,
+        let missing = req
-        sigma: Option<f64>,
+            .missing
-        accessor_idx: usize,
+            .and_then(|val| f64_to_fastfield_u64(val, &req.field_type));
-        missing: Option<f64>,
-    ) -> Self {
-        let missing = missing.and_then(|val| f64_to_fastfield_u64(val, &field_type));
         Self {
-            field_type,
+            name: req.name.clone(),
-            extended_stats: IntermediateExtendedStats::with_sigma(sigma),
+            field_type: req.field_type,
-            accessor_idx,
+            accessor: req.accessor.clone(),
             missing,
-            val_cache: Default::default(),
+            buckets: vec![IntermediateExtendedStats::with_sigma(sigma); 16],
-        }
+            sigma,
-    }
-    #[inline]
-    pub(crate) fn collect_block_with_field(
-        &mut self,
-        docs: &[DocId],
-        req_data: &mut MetricAggReqData,
-    ) {
-        if let Some(missing) = self.missing.as_ref() {
-            req_data.column_block_accessor.fetch_block_with_missing(
-                docs,
-                &req_data.accessor,
-                *missing,
-            );
-        } else {
-            req_data
-                .column_block_accessor
-                .fetch_block(docs, &req_data.accessor);
-        }
-        for val in req_data.column_block_accessor.iter_vals() {
-            let val1 = f64_from_fastfield_u64(val, &self.field_type);
-            self.extended_stats.collect(val1);
         }
     }
 }
@@ -370,15 +346,18 @@ impl SegmentExtendedStatsCollector {
 impl SegmentAggregationCollector for SegmentExtendedStatsCollector {
     #[inline]
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
-        let name = agg_data.get_metric_req_data(self.accessor_idx).name.clone();
+        let name = self.name.clone();
+        self.prepare_max_bucket(parent_bucket_id, agg_data)?;
+        let extended_stats = std::mem::take(&mut self.buckets[parent_bucket_id as usize]);
         results.push(
             name,
             IntermediateAggregationResult::Metric(IntermediateMetricResult::ExtendedStats(
-                self.extended_stats,
+                extended_stats,
             )),
         )?;
 
@@ -388,39 +367,36 @@ impl SegmentAggregationCollector for SegmentExtendedStatsCollector {
     #[inline]
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
+        docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        let req_data = agg_data.get_metric_req_data(self.accessor_idx);
+        let mut extended_stats = self.buckets[parent_bucket_id as usize].clone();
-        if let Some(missing) = self.missing {
+
-            let mut has_val = false;
+        agg_data
-            for val in req_data.accessor.values_for_doc(doc) {
+            .column_block_accessor
-                let val1 = f64_from_fastfield_u64(val, &self.field_type);
+            .fetch_block_with_missing(docs, &self.accessor, self.missing);
-                self.extended_stats.collect(val1);
+        for val in agg_data.column_block_accessor.iter_vals() {
-                has_val = true;
+            let val1 = f64_from_fastfield_u64(val, self.field_type);
-            }
+            extended_stats.collect(val1);
-            if !has_val {
-                self.extended_stats
-                    .collect(f64_from_fastfield_u64(missing, &self.field_type));
-            }
-        } else {
-            for val in req_data.accessor.values_for_doc(doc) {
-                let val1 = f64_from_fastfield_u64(val, &self.field_type);
-                self.extended_stats.collect(val1);
-            }
         }
 
+        // store back
+        self.buckets[parent_bucket_id as usize] = extended_stats;
+
         Ok(())
     }
 
-    #[inline]
+    fn prepare_max_bucket(
-    fn collect_block(
         &mut self,
-        docs: &[crate::DocId],
+        max_bucket: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
+        _agg_data: &AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        let req_data = agg_data.get_metric_req_data_mut(self.accessor_idx);
+        if self.buckets.len() <= max_bucket as usize {
-        self.collect_block_with_field(docs, req_data);
+            self.buckets.resize_with(max_bucket as usize + 1, || {
+                IntermediateExtendedStats::with_sigma(self.sigma)
+            });
+        }
         Ok(())
     }
 }

src/aggregation/metric/max.rs

@@ -52,10 +52,8 @@ pub struct IntermediateMax {
 
 impl IntermediateMax {
     /// Creates a new [`IntermediateMax`] instance from a [`SegmentStatsCollector`].
-    pub(crate) fn from_collector(collector: SegmentStatsCollector) -> Self {
+    pub(crate) fn from_stats(stats: IntermediateStats) -> Self {
-        Self {
+        Self { stats }
-            stats: collector.stats,
-        }
     }
     /// Merges the other intermediate result into self.
     pub fn merge_fruits(&mut self, other: IntermediateMax) {

src/aggregation/metric/min.rs

@@ -52,10 +52,8 @@ pub struct IntermediateMin {
 
 impl IntermediateMin {
     /// Creates a new [`IntermediateMin`] instance from a [`SegmentStatsCollector`].
-    pub(crate) fn from_collector(collector: SegmentStatsCollector) -> Self {
+    pub(crate) fn from_stats(stats: IntermediateStats) -> Self {
-        Self {
+        Self { stats }
-            stats: collector.stats,
-        }
     }
     /// Merges the other intermediate result into self.
     pub fn merge_fruits(&mut self, other: IntermediateMin) {

src/aggregation/metric/mod.rs

@@ -31,7 +31,7 @@ use std::collections::HashMap;
 
 pub use average::*;
 pub use cardinality::*;
-use columnar::{Column, ColumnBlockAccessor, ColumnType};
+use columnar::{Column, ColumnType};
 pub use count::*;
 pub use extended_stats::*;
 pub use max::*;
@@ -55,8 +55,6 @@ pub struct MetricAggReqData {
     pub field_type: ColumnType,
     /// The missing value normalized to the internal u64 representation of the field type.
     pub missing_u64: Option<u64>,
-    /// The column block accessor to access the fast field values.
-    pub column_block_accessor: ColumnBlockAccessor<u64>,
     /// The column accessor to access the fast field values.
     pub accessor: Column<u64>,
     /// Used when converting to intermediate result

src/aggregation/metric/percentiles.rs

@@ -7,10 +7,9 @@ use crate::aggregation::agg_data::AggregationsSegmentCtx;
 use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateAggregationResults, IntermediateMetricResult,
 };
-use crate::aggregation::metric::MetricAggReqData;
 use crate::aggregation::segment_agg_result::SegmentAggregationCollector;
 use crate::aggregation::*;
-use crate::{DocId, TantivyError};
+use crate::TantivyError;
 
 /// # Percentiles
 ///
@@ -131,10 +130,16 @@ impl PercentilesAggregationReq {
     }
 }
 
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Debug)]
 pub(crate) struct SegmentPercentilesCollector {
-    pub(crate) percentiles: PercentilesCollector,
+    pub(crate) buckets: Vec<PercentilesCollector>,
     pub(crate) accessor_idx: usize,
+    /// The type of the field.
+    pub field_type: ColumnType,
+    /// The missing value normalized to the internal u64 representation of the field type.
+    pub missing_u64: Option<u64>,
+    /// The column accessor to access the fast field values.
+    pub accessor: Column<u64>,
 }
 
 #[derive(Clone, Serialize, Deserialize)]
@@ -229,33 +234,18 @@ impl PercentilesCollector {
 }
 
 impl SegmentPercentilesCollector {
-    pub fn from_req_and_validate(accessor_idx: usize) -> crate::Result<Self> {
+    pub fn from_req_and_validate(
-        Ok(Self {
+        field_type: ColumnType,
-            percentiles: PercentilesCollector::new(),
+        missing_u64: Option<u64>,
+        accessor: Column<u64>,
+        accessor_idx: usize,
+    ) -> Self {
+        Self {
+            buckets: Vec::with_capacity(64),
+            field_type,
+            missing_u64,
+            accessor,
             accessor_idx,
-        })
-    }
-    #[inline]
-    pub(crate) fn collect_block_with_field(
-        &mut self,
-        docs: &[DocId],
-        req_data: &mut MetricAggReqData,
-    ) {
-        if let Some(missing) = req_data.missing_u64.as_ref() {
-            req_data.column_block_accessor.fetch_block_with_missing(
-                docs,
-                &req_data.accessor,
-                *missing,
-            );
-        } else {
-            req_data
-                .column_block_accessor
-                .fetch_block(docs, &req_data.accessor);
-        }
-
-        for val in req_data.column_block_accessor.iter_vals() {
-            let val1 = f64_from_fastfield_u64(val, &req_data.field_type);
-            self.percentiles.collect(val1);
         }
     }
 }
@@ -263,12 +253,18 @@ impl SegmentPercentilesCollector {
 impl SegmentAggregationCollector for SegmentPercentilesCollector {
     #[inline]
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
         let name = agg_data.get_metric_req_data(self.accessor_idx).name.clone();
-        let intermediate_metric_result = IntermediateMetricResult::Percentiles(self.percentiles);
+        self.prepare_max_bucket(parent_bucket_id, agg_data)?;
+        // Swap collector with an empty one to avoid cloning
+        let percentiles_collector = std::mem::take(&mut self.buckets[parent_bucket_id as usize]);
+
+        let intermediate_metric_result =
+            IntermediateMetricResult::Percentiles(percentiles_collector);
 
         results.push(
             name,
@@ -281,40 +277,33 @@ impl SegmentAggregationCollector for SegmentPercentilesCollector {
     #[inline]
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
+        docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        let req_data = agg_data.get_metric_req_data(self.accessor_idx);
+        let percentiles = &mut self.buckets[parent_bucket_id as usize];
+        agg_data.column_block_accessor.fetch_block_with_missing(
+            docs,
+            &self.accessor,
+            self.missing_u64,
+        );
 
-        if let Some(missing) = req_data.missing_u64 {
+        for val in agg_data.column_block_accessor.iter_vals() {
-            let mut has_val = false;
+            let val1 = f64_from_fastfield_u64(val, self.field_type);
-            for val in req_data.accessor.values_for_doc(doc) {
+            percentiles.collect(val1);
-                let val1 = f64_from_fastfield_u64(val, &req_data.field_type);
-                self.percentiles.collect(val1);
-                has_val = true;
-            }
-            if !has_val {
-                self.percentiles
-                    .collect(f64_from_fastfield_u64(missing, &req_data.field_type));
-            }
-        } else {
-            for val in req_data.accessor.values_for_doc(doc) {
-                let val1 = f64_from_fastfield_u64(val, &req_data.field_type);
-                self.percentiles.collect(val1);
-            }
         }
 
         Ok(())
     }
 
-    #[inline]
+    fn prepare_max_bucket(
-    fn collect_block(
         &mut self,
-        docs: &[crate::DocId],
+        max_bucket: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
+        _agg_data: &AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        let req_data = agg_data.get_metric_req_data_mut(self.accessor_idx);
+        while self.buckets.len() <= max_bucket as usize {
-        self.collect_block_with_field(docs, req_data);
+            self.buckets.push(PercentilesCollector::new());
+        }
         Ok(())
     }
 }

src/aggregation/metric/stats.rs

@@ -1,5 +1,6 @@
 use std::fmt::Debug;
 
+use columnar::{Column, ColumnType};
 use serde::{Deserialize, Serialize};
 
 use super::*;
@@ -7,10 +8,9 @@ use crate::aggregation::agg_data::AggregationsSegmentCtx;
 use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateAggregationResults, IntermediateMetricResult,
 };
-use crate::aggregation::metric::MetricAggReqData;
 use crate::aggregation::segment_agg_result::SegmentAggregationCollector;
 use crate::aggregation::*;
-use crate::{DocId, TantivyError};
+use crate::TantivyError;
 
 /// A multi-value metric aggregation that computes a collection of statistics on numeric values that
 /// are extracted from the aggregated documents.
@@ -83,7 +83,7 @@ impl Stats {
 
 /// Intermediate result of the stats aggregation that can be combined with other intermediate
 /// results.
-#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+#[derive(Clone, Copy, Debug, PartialEq, Serialize, Deserialize)]
 pub struct IntermediateStats {
     /// The number of extracted values.
     pub(crate) count: u64,
@@ -187,75 +187,75 @@ pub enum StatsType {
     Percentiles,
 }
 
+fn create_collector<const TYPE_ID: u8>(
+    req: &MetricAggReqData,
+) -> Box<dyn SegmentAggregationCollector> {
+    Box::new(SegmentStatsCollector::<TYPE_ID> {
+        name: req.name.clone(),
+        collecting_for: req.collecting_for,
+        is_number_or_date_type: req.is_number_or_date_type,
+        missing_u64: req.missing_u64,
+        accessor: req.accessor.clone(),
+        buckets: vec![IntermediateStats::default()],
+    })
+}
+
+/// Build a concrete `SegmentStatsCollector` depending on the column type.
+pub(crate) fn build_segment_stats_collector(
+    req: &MetricAggReqData,
+) -> crate::Result<Box<dyn SegmentAggregationCollector>> {
+    match req.field_type {
+        ColumnType::I64 => Ok(create_collector::<{ ColumnType::I64 as u8 }>(req)),
+        ColumnType::U64 => Ok(create_collector::<{ ColumnType::U64 as u8 }>(req)),
+        ColumnType::F64 => Ok(create_collector::<{ ColumnType::F64 as u8 }>(req)),
+        ColumnType::Bool => Ok(create_collector::<{ ColumnType::Bool as u8 }>(req)),
+        ColumnType::DateTime => Ok(create_collector::<{ ColumnType::DateTime as u8 }>(req)),
+        ColumnType::Bytes => Ok(create_collector::<{ ColumnType::Bytes as u8 }>(req)),
+        ColumnType::Str => Ok(create_collector::<{ ColumnType::Str as u8 }>(req)),
+        ColumnType::IpAddr => Ok(create_collector::<{ ColumnType::IpAddr as u8 }>(req)),
+    }
+}
+
+#[repr(C)]
 #[derive(Clone, Debug)]
-pub(crate) struct SegmentStatsCollector {
+pub(crate) struct SegmentStatsCollector<const COLUMN_TYPE_ID: u8> {
-    pub(crate) stats: IntermediateStats,
+    pub(crate) missing_u64: Option<u64>,
-    pub(crate) accessor_idx: usize,
+    pub(crate) accessor: Column<u64>,
+    pub(crate) is_number_or_date_type: bool,
+    pub(crate) buckets: Vec<IntermediateStats>,
+    pub(crate) name: String,
+    pub(crate) collecting_for: StatsType,
 }
 
-impl SegmentStatsCollector {
+impl<const COLUMN_TYPE_ID: u8> SegmentAggregationCollector
-    pub fn from_req(accessor_idx: usize) -> Self {
+    for SegmentStatsCollector<COLUMN_TYPE_ID>
-        Self {
+{
-            stats: IntermediateStats::default(),
-            accessor_idx,
-        }
-    }
-    #[inline]
-    pub(crate) fn collect_block_with_field(
-        &mut self,
-        docs: &[DocId],
-        req_data: &mut MetricAggReqData,
-    ) {
-        if let Some(missing) = req_data.missing_u64.as_ref() {
-            req_data.column_block_accessor.fetch_block_with_missing(
-                docs,
-                &req_data.accessor,
-                *missing,
-            );
-        } else {
-            req_data
-                .column_block_accessor
-                .fetch_block(docs, &req_data.accessor);
-        }
-        if req_data.is_number_or_date_type {
-            for val in req_data.column_block_accessor.iter_vals() {
-                let val1 = f64_from_fastfield_u64(val, &req_data.field_type);
-                self.stats.collect(val1);
-            }
-        } else {
-            for _val in req_data.column_block_accessor.iter_vals() {
-                // we ignore the value and simply record that we got something
-                self.stats.collect(0.0);
-            }
-        }
-    }
-}
-
-impl SegmentAggregationCollector for SegmentStatsCollector {
     #[inline]
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
-        let req = agg_data.get_metric_req_data(self.accessor_idx);
+        let name = self.name.clone();
-        let name = req.name.clone();
 
-        let intermediate_metric_result = match req.collecting_for {
+        self.prepare_max_bucket(parent_bucket_id, agg_data)?;
+        let stats = self.buckets[parent_bucket_id as usize];
+        let intermediate_metric_result = match self.collecting_for {
             StatsType::Average => {
-                IntermediateMetricResult::Average(IntermediateAverage::from_collector(*self))
+                IntermediateMetricResult::Average(IntermediateAverage::from_stats(stats))
             }
             StatsType::Count => {
-                IntermediateMetricResult::Count(IntermediateCount::from_collector(*self))
+                IntermediateMetricResult::Count(IntermediateCount::from_stats(stats))
             }
-            StatsType::Max => IntermediateMetricResult::Max(IntermediateMax::from_collector(*self)),
+            StatsType::Max => IntermediateMetricResult::Max(IntermediateMax::from_stats(stats)),
-            StatsType::Min => IntermediateMetricResult::Min(IntermediateMin::from_collector(*self)),
+            StatsType::Min => IntermediateMetricResult::Min(IntermediateMin::from_stats(stats)),
-            StatsType::Stats => IntermediateMetricResult::Stats(self.stats),
+            StatsType::Stats => IntermediateMetricResult::Stats(stats),
-            StatsType::Sum => IntermediateMetricResult::Sum(IntermediateSum::from_collector(*self)),
+            StatsType::Sum => IntermediateMetricResult::Sum(IntermediateSum::from_stats(stats)),
             _ => {
                 return Err(TantivyError::InvalidArgument(format!(
                     "Unsupported stats type for stats aggregation: {:?}",
-                    req.collecting_for
+                    self.collecting_for
                 )))
             }
         };
@@ -271,41 +271,67 @@ impl SegmentAggregationCollector for SegmentStatsCollector {
     #[inline]
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        let req_data = agg_data.get_metric_req_data(self.accessor_idx);
-        if let Some(missing) = req_data.missing_u64 {
-            let mut has_val = false;
-            for val in req_data.accessor.values_for_doc(doc) {
-                let val1 = f64_from_fastfield_u64(val, &req_data.field_type);
-                self.stats.collect(val1);
-                has_val = true;
-            }
-            if !has_val {
-                self.stats
-                    .collect(f64_from_fastfield_u64(missing, &req_data.field_type));
-            }
-        } else {
-            for val in req_data.accessor.values_for_doc(doc) {
-                let val1 = f64_from_fastfield_u64(val, &req_data.field_type);
-                self.stats.collect(val1);
-            }
-        }
-
-        Ok(())
-    }
-
-    #[inline]
-    fn collect_block(
-        &mut self,
         docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
-        let req_data = agg_data.get_metric_req_data_mut(self.accessor_idx);
+        // TODO: remove once we fetch all values for all bucket ids in one go
-        self.collect_block_with_field(docs, req_data);
+        if docs.len() == 1 && self.missing_u64.is_none() {
+            collect_stats::<COLUMN_TYPE_ID>(
+                &mut self.buckets[parent_bucket_id as usize],
+                self.accessor.values_for_doc(docs[0]),
+                self.is_number_or_date_type,
+            )?;
+
+            return Ok(());
+        }
+        agg_data.column_block_accessor.fetch_block_with_missing(
+            docs,
+            &self.accessor,
+            self.missing_u64,
+        );
+        collect_stats::<COLUMN_TYPE_ID>(
+            &mut self.buckets[parent_bucket_id as usize],
+            agg_data.column_block_accessor.iter_vals(),
+            self.is_number_or_date_type,
+        )?;
+
         Ok(())
     }
+
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        _agg_data: &AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        let required_buckets = (max_bucket as usize) + 1;
+        if self.buckets.len() < required_buckets {
+            self.buckets
+                .resize_with(required_buckets, IntermediateStats::default);
+        }
+        Ok(())
+    }
+}
+
+#[inline]
+fn collect_stats<const COLUMN_TYPE_ID: u8>(
+    stats: &mut IntermediateStats,
+    vals: impl Iterator<Item = u64>,
+    is_number_or_date_type: bool,
+) -> crate::Result<()> {
+    if is_number_or_date_type {
+        for val in vals {
+            let val1 = convert_to_f64::<COLUMN_TYPE_ID>(val);
+            stats.collect(val1);
+        }
+    } else {
+        for _val in vals {
+            // we ignore the value and simply record that we got something
+            stats.collect(0.0);
+        }
+    }
+
+    Ok(())
 }
 
 #[cfg(test)]

src/aggregation/metric/sum.rs

@@ -52,10 +52,8 @@ pub struct IntermediateSum {
 
 impl IntermediateSum {
     /// Creates a new [`IntermediateSum`] instance from a [`SegmentStatsCollector`].
-    pub(crate) fn from_collector(collector: SegmentStatsCollector) -> Self {
+    pub(crate) fn from_stats(stats: IntermediateStats) -> Self {
-        Self {
+        Self { stats }
-            stats: collector.stats,
-        }
     }
     /// Merges the other intermediate result into self.
     pub fn merge_fruits(&mut self, other: IntermediateSum) {

src/aggregation/metric/top_hits.rs

@@ -15,12 +15,11 @@ use crate::aggregation::intermediate_agg_result::{
     IntermediateAggregationResult, IntermediateMetricResult,
 };
 use crate::aggregation::segment_agg_result::SegmentAggregationCollector;
-use crate::aggregation::AggregationError;
+use crate::aggregation::{AggregationError, BucketId};
 use crate::collector::sort_key::ReverseComparator;
 use crate::collector::TopNComputer;
 use crate::schema::OwnedValue;
 use crate::{DocAddress, DocId, SegmentOrdinal};
-// duplicate import removed; already imported above
 
 /// Contains all information required by the TopHitsSegmentCollector to perform the
 /// top_hits aggregation on a segment.
@@ -472,7 +471,10 @@ impl TopHitsTopNComputer {
     /// Create a new TopHitsCollector
     pub fn new(req: &TopHitsAggregationReq) -> Self {
         Self {
-            top_n: TopNComputer::new(req.size + req.from.unwrap_or(0)),
+            top_n: TopNComputer::new_with_comparator(
+                req.size + req.from.unwrap_or(0),
+                ReverseComparator,
+            ),
             req: req.clone(),
         }
     }
@@ -518,7 +520,8 @@ impl TopHitsTopNComputer {
 pub(crate) struct TopHitsSegmentCollector {
     segment_ordinal: SegmentOrdinal,
     accessor_idx: usize,
-    top_n: TopNComputer<Vec<DocValueAndOrder>, DocAddress, ReverseComparator>,
+    buckets: Vec<TopNComputer<Vec<DocValueAndOrder>, DocAddress, ReverseComparator>>,
+    num_hits: usize,
 }
 
 impl TopHitsSegmentCollector {
@@ -527,19 +530,29 @@ impl TopHitsSegmentCollector {
         accessor_idx: usize,
         segment_ordinal: SegmentOrdinal,
     ) -> Self {
+        let num_hits = req.size + req.from.unwrap_or(0);
         Self {
-            top_n: TopNComputer::new(req.size + req.from.unwrap_or(0)),
+            num_hits,
             segment_ordinal,
             accessor_idx,
+            buckets: vec![TopNComputer::new_with_comparator(num_hits, ReverseComparator); 1],
         }
     }
-    fn into_top_hits_collector(
+    fn get_top_hits_computer(
-        self,
+        &mut self,
+        parent_bucket_id: BucketId,
         value_accessors: &HashMap<String, Vec<DynamicColumn>>,
         req: &TopHitsAggregationReq,
     ) -> TopHitsTopNComputer {
+        if parent_bucket_id as usize >= self.buckets.len() {
+            return TopHitsTopNComputer::new(req);
+        }
+        let top_n = std::mem::replace(
+            &mut self.buckets[parent_bucket_id as usize],
+            TopNComputer::new(0),
+        );
         let mut top_hits_computer = TopHitsTopNComputer::new(req);
-        let top_results = self.top_n.into_vec();
+        let top_results = top_n.into_vec();
 
         for res in top_results {
             let doc_value_fields = req.get_document_field_data(value_accessors, res.doc.doc_id);
@@ -554,54 +567,24 @@ impl TopHitsSegmentCollector {
 
         top_hits_computer
     }
-
-    /// TODO add a specialized variant for a single sort field
-    fn collect_with(
-        &mut self,
-        doc_id: crate::DocId,
-        req: &TopHitsAggregationReq,
-        accessors: &[(Column<u64>, ColumnType)],
-    ) -> crate::Result<()> {
-        let sorts: Vec<DocValueAndOrder> = req
-            .sort
-            .iter()
-            .enumerate()
-            .map(|(idx, KeyOrder { order, .. })| {
-                let order = *order;
-                let value = accessors
-                    .get(idx)
-                    .expect("could not find field in accessors")
-                    .0
-                    .values_for_doc(doc_id)
-                    .next();
-                DocValueAndOrder { value, order }
-            })
-            .collect();
-
-        self.top_n.push(
-            sorts,
-            DocAddress {
-                segment_ord: self.segment_ordinal,
-                doc_id,
-            },
-        );
-        Ok(())
-    }
 }
 
 impl SegmentAggregationCollector for TopHitsSegmentCollector {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut crate::aggregation::intermediate_agg_result::IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
         let req_data = agg_data.get_top_hits_req_data(self.accessor_idx);
 
         let value_accessors = &req_data.value_accessors;
 
-        let intermediate_result = IntermediateMetricResult::TopHits(
+        let intermediate_result = IntermediateMetricResult::TopHits(self.get_top_hits_computer(
-            self.into_top_hits_collector(value_accessors, &req_data.req),
+            parent_bucket_id,
-        );
+            value_accessors,
+            &req_data.req,
+        ));
         results.push(
             req_data.name.to_string(),
             IntermediateAggregationResult::Metric(intermediate_result),
@@ -611,26 +594,56 @@ impl SegmentAggregationCollector for TopHitsSegmentCollector {
     /// TODO: Consider a caching layer to reduce the call overhead
     fn collect(
         &mut self,
-        doc_id: crate::DocId,
+        parent_bucket_id: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        let req_data = agg_data.get_top_hits_req_data(self.accessor_idx);
-        self.collect_with(doc_id, &req_data.req, &req_data.accessors)?;
-        Ok(())
-    }
-
-    fn collect_block(
-        &mut self,
         docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
+        let top_n = &mut self.buckets[parent_bucket_id as usize];
         let req_data = agg_data.get_top_hits_req_data(self.accessor_idx);
-        // TODO: Consider getting fields with the column block accessor.
+        let req = &req_data.req;
-        for doc in docs {
+        let accessors = &req_data.accessors;
-            self.collect_with(*doc, &req_data.req, &req_data.accessors)?;
+        for &doc_id in docs {
+            // TODO: this is terrible, a new vec is allocated for every doc
+            // We can fetch blocks instead
+            // We don't need to store the order for every value
+            let sorts: Vec<DocValueAndOrder> = req
+                .sort
+                .iter()
+                .enumerate()
+                .map(|(idx, KeyOrder { order, .. })| {
+                    let order = *order;
+                    let value = accessors
+                        .get(idx)
+                        .expect("could not find field in accessors")
+                        .0
+                        .values_for_doc(doc_id)
+                        .next();
+                    DocValueAndOrder { value, order }
+                })
+                .collect();
+
+            top_n.push(
+                sorts,
+                DocAddress {
+                    segment_ord: self.segment_ordinal,
+                    doc_id,
+                },
+            );
         }
         Ok(())
     }
+
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        _agg_data: &AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        self.buckets.resize(
+            (max_bucket as usize) + 1,
+            TopNComputer::new_with_comparator(self.num_hits, ReverseComparator),
+        );
+        Ok(())
+    }
 }
 
 #[cfg(test)]
@@ -746,7 +759,7 @@ mod tests {
                     ],
                     "from": 0,
                 }
-        }
+            }
         }))
         .unwrap();
 
@@ -875,7 +888,7 @@ mod tests {
                         "mixed.*",
                     ],
                 }
-        }
+            }
         }))?;
 
         let collector = AggregationCollector::from_aggs(d, Default::default());

src/aggregation/mod.rs

@@ -133,7 +133,7 @@ mod agg_limits;
 pub mod agg_req;
 pub mod agg_result;
 pub mod bucket;
-mod buf_collector;
+pub(crate) mod cached_sub_aggs;
 mod collector;
 mod date;
 mod error;
@@ -162,6 +162,19 @@ use serde::{Deserialize, Deserializer, Serialize};
 
 use crate::tokenizer::TokenizerManager;
 
+/// A bucket id is a dense identifier for a bucket within an aggregation.
+/// It is used to index into a Vec that hold per-bucket data.
+///
+/// For example, in a terms aggregation, each unique term will be assigned a incremental BucketId.
+/// This BucketId will be forwarded to sub-aggregations to identify the parent bucket.
+///
+/// This allows to have a single AggregationCollector instance per aggregation,
+/// that can handle multiple buckets efficiently.
+///
+/// The API to call sub-aggregations is therefore a &[(BucketId, &[DocId])].
+/// For that we'll need a buffer. One Vec per bucket aggregation is needed.
+pub type BucketId = u32;
+
 /// Context parameters for aggregation execution
 ///
 /// This struct holds shared resources needed during aggregation execution:
@@ -335,19 +348,37 @@ impl Display for Key {
     }
 }
 
+pub(crate) fn convert_to_f64<const COLUMN_TYPE_ID: u8>(val: u64) -> f64 {
+    if COLUMN_TYPE_ID == ColumnType::U64 as u8 {
+        val as f64
+    } else if COLUMN_TYPE_ID == ColumnType::I64 as u8
+        || COLUMN_TYPE_ID == ColumnType::DateTime as u8
+    {
+        i64::from_u64(val) as f64
+    } else if COLUMN_TYPE_ID == ColumnType::F64 as u8 {
+        f64::from_u64(val)
+    } else if COLUMN_TYPE_ID == ColumnType::Bool as u8 {
+        val as f64
+    } else {
+        panic!(
+            "ColumnType ID {} cannot be converted to f64 metric",
+            COLUMN_TYPE_ID
+        )
+    }
+}
+
 /// Inverse of `to_fastfield_u64`. Used to convert to `f64` for metrics.
 ///
 /// # Panics
 /// Only `u64`, `f64`, `date`, and `i64` are supported.
-pub(crate) fn f64_from_fastfield_u64(val: u64, field_type: &ColumnType) -> f64 {
+pub(crate) fn f64_from_fastfield_u64(val: u64, field_type: ColumnType) -> f64 {
     match field_type {
-        ColumnType::U64 => val as f64,
+        ColumnType::U64 => convert_to_f64::<{ ColumnType::U64 as u8 }>(val),
-        ColumnType::I64 | ColumnType::DateTime => i64::from_u64(val) as f64,
+        ColumnType::I64 => convert_to_f64::<{ ColumnType::I64 as u8 }>(val),
-        ColumnType::F64 => f64::from_u64(val),
+        ColumnType::F64 => convert_to_f64::<{ ColumnType::F64 as u8 }>(val),
-        ColumnType::Bool => val as f64,
+        ColumnType::Bool => convert_to_f64::<{ ColumnType::Bool as u8 }>(val),
-        _ => {
+        ColumnType::DateTime => convert_to_f64::<{ ColumnType::DateTime as u8 }>(val),
-            panic!("unexpected type {field_type:?}. This should not happen")
+        _ => panic!("unexpected type {field_type:?}. This should not happen"),
-        }
     }
 }
 

src/aggregation/segment_agg_result.rs

@@ -8,25 +8,67 @@ use std::fmt::Debug;
 pub(crate) use super::agg_limits::AggregationLimitsGuard;
 use super::intermediate_agg_result::IntermediateAggregationResults;
 use crate::aggregation::agg_data::AggregationsSegmentCtx;
+use crate::aggregation::BucketId;
+
+/// Monotonically increasing provider of BucketIds.
+#[derive(Debug, Clone, Default)]
+pub struct BucketIdProvider(u32);
+impl BucketIdProvider {
+    /// Get the next BucketId.
+    pub fn next_bucket_id(&mut self) -> BucketId {
+        let bucket_id = self.0;
+        self.0 += 1;
+        bucket_id
+    }
+}
 
 /// A SegmentAggregationCollector is used to collect aggregation results.
-pub trait SegmentAggregationCollector: CollectorClone + Debug {
+pub trait SegmentAggregationCollector: Debug {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()>;
 
+    /// Note: The caller needs to call `prepare_max_bucket` before calling `collect`.
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
+        docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()>;
 
-    fn collect_block(
+    /// Collect docs for multiple buckets in one call.
+    /// Minimizes dynamic dispatch overhead when collecting many buckets.
+    ///
+    /// Note: The caller needs to call `prepare_max_bucket` before calling `collect`.
+    fn collect_multiple(
         &mut self,
+        bucket_ids: &[BucketId],
         docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        debug_assert_eq!(bucket_ids.len(), docs.len());
+        let mut start = 0;
+        while start < bucket_ids.len() {
+            let bucket_id = bucket_ids[start];
+            let mut end = start + 1;
+            while end < bucket_ids.len() && bucket_ids[end] == bucket_id {
+                end += 1;
+            }
+            self.collect(bucket_id, &docs[start..end], agg_data)?;
+            start = end;
+        }
+        Ok(())
+    }
+
+    /// Prepare the collector for collecting up to BucketId `max_bucket`.
+    /// This is useful so we can split allocation ahead of time of collecting.
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        agg_data: &AggregationsSegmentCtx,
     ) -> crate::Result<()>;
 
     /// Finalize method. Some Aggregator collect blocks of docs before calling `collect_block`.
@@ -36,26 +78,7 @@ pub trait SegmentAggregationCollector: CollectorClone + Debug {
     }
 }
 
-/// A helper trait to enable cloning of Box<dyn SegmentAggregationCollector>
+#[derive(Default)]
-pub trait CollectorClone {
-    fn clone_box(&self) -> Box<dyn SegmentAggregationCollector>;
-}
-
-impl<T> CollectorClone for T
-where T: 'static + SegmentAggregationCollector + Clone
-{
-    fn clone_box(&self) -> Box<dyn SegmentAggregationCollector> {
-        Box::new(self.clone())
-    }
-}
-
-impl Clone for Box<dyn SegmentAggregationCollector> {
-    fn clone(&self) -> Box<dyn SegmentAggregationCollector> {
-        self.clone_box()
-    }
-}
-
-#[derive(Clone, Default)]
 /// The GenericSegmentAggregationResultsCollector is the generic version of the collector, which
 /// can handle arbitrary complexity of  sub-aggregations. Ideally we never have to pick this one
 /// and can provide specialized versions instead, that remove some of its overhead.
@@ -73,12 +96,13 @@ impl Debug for GenericSegmentAggregationResultsCollector {
 
 impl SegmentAggregationCollector for GenericSegmentAggregationResultsCollector {
     fn add_intermediate_aggregation_result(
-        self: Box<Self>,
+        &mut self,
         agg_data: &AggregationsSegmentCtx,
         results: &mut IntermediateAggregationResults,
+        parent_bucket_id: BucketId,
     ) -> crate::Result<()> {
-        for agg in self.aggs {
+        for agg in &mut self.aggs {
-            agg.add_intermediate_aggregation_result(agg_data, results)?;
+            agg.add_intermediate_aggregation_result(agg_data, results, parent_bucket_id)?;
         }
 
         Ok(())
@@ -86,23 +110,13 @@ impl SegmentAggregationCollector for GenericSegmentAggregationResultsCollector {
 
     fn collect(
         &mut self,
-        doc: crate::DocId,
+        parent_bucket_id: BucketId,
-        agg_data: &mut AggregationsSegmentCtx,
-    ) -> crate::Result<()> {
-        self.collect_block(&[doc], agg_data)?;
-
-        Ok(())
-    }
-
-    fn collect_block(
-        &mut self,
         docs: &[crate::DocId],
         agg_data: &mut AggregationsSegmentCtx,
     ) -> crate::Result<()> {
         for collector in &mut self.aggs {
-            collector.collect_block(docs, agg_data)?;
+            collector.collect(parent_bucket_id, docs, agg_data)?;
         }
-
         Ok(())
     }
 
@@ -112,4 +126,15 @@ impl SegmentAggregationCollector for GenericSegmentAggregationResultsCollector {
         }
         Ok(())
     }
+
+    fn prepare_max_bucket(
+        &mut self,
+        max_bucket: BucketId,
+        agg_data: &AggregationsSegmentCtx,
+    ) -> crate::Result<()> {
+        for collector in &mut self.aggs {
+            collector.prepare_max_bucket(max_bucket, agg_data)?;
+        }
+        Ok(())
+    }
 }

src/collector/sort_key/mod.rs

@@ -1,10 +1,12 @@
 mod order;
+mod sort_by_erased_type;
 mod sort_by_score;
 mod sort_by_static_fast_value;
 mod sort_by_string;
 mod sort_key_computer;
 
 pub use order::*;
+pub use sort_by_erased_type::SortByErasedType;
 pub use sort_by_score::SortBySimilarityScore;
 pub use sort_by_static_fast_value::SortByStaticFastValue;
 pub use sort_by_string::SortByString;
@@ -34,11 +36,13 @@ pub(crate) mod tests {
     use std::collections::HashMap;
     use std::ops::Range;
 
-    use crate::collector::sort_key::{SortBySimilarityScore, SortByStaticFastValue, SortByString};
+    use crate::collector::sort_key::{
+        SortByErasedType, SortBySimilarityScore, SortByStaticFastValue, SortByString,
+    };
     use crate::collector::{ComparableDoc, DocSetCollector, TopDocs};
     use crate::indexer::NoMergePolicy;
     use crate::query::{AllQuery, QueryParser};
-    use crate::schema::{Schema, FAST, TEXT};
+    use crate::schema::{OwnedValue, Schema, FAST, TEXT};
     use crate::{DocAddress, Document, Index, Order, Score, Searcher};
 
     fn make_index() -> crate::Result<Index> {
@@ -313,11 +317,9 @@ pub(crate) mod tests {
                 (SortBySimilarityScore, score_order),
                 (SortByString::for_field("city"), city_order),
             ));
-            Ok(searcher
+            let results: Vec<((Score, Option<String>), DocAddress)> =
-                .search(&AllQuery, &top_collector)?
+                searcher.search(&AllQuery, &top_collector)?;
-                .into_iter()
+            Ok(results.into_iter().map(|(f, doc)| (f, ids[&doc])).collect())
-                .map(|(f, doc)| (f, ids[&doc]))
-                .collect())
         }
 
         assert_eq!(
@@ -342,6 +344,51 @@ pub(crate) mod tests {
         Ok(())
     }
 
+    #[test]
+    fn test_order_by_score_then_owned_value() -> crate::Result<()> {
+        let index = make_index()?;
+
+        type SortKey = (Score, OwnedValue);
+
+        fn query(
+            index: &Index,
+            score_order: Order,
+            city_order: Order,
+        ) -> crate::Result<Vec<(SortKey, u64)>> {
+            let searcher = index.reader()?.searcher();
+            let ids = id_mapping(&searcher);
+
+            let top_collector = TopDocs::with_limit(4).order_by::<(Score, OwnedValue)>((
+                (SortBySimilarityScore, score_order),
+                (SortByErasedType::for_field("city"), city_order),
+            ));
+            let results: Vec<((Score, OwnedValue), DocAddress)> =
+                searcher.search(&AllQuery, &top_collector)?;
+            Ok(results.into_iter().map(|(f, doc)| (f, ids[&doc])).collect())
+        }
+
+        assert_eq!(
+            &query(&index, Order::Asc, Order::Asc)?,
+            &[
+                ((1.0, OwnedValue::Str("austin".to_owned())), 0),
+                ((1.0, OwnedValue::Str("greenville".to_owned())), 1),
+                ((1.0, OwnedValue::Str("tokyo".to_owned())), 2),
+                ((1.0, OwnedValue::Null), 3),
+            ]
+        );
+
+        assert_eq!(
+            &query(&index, Order::Asc, Order::Desc)?,
+            &[
+                ((1.0, OwnedValue::Str("tokyo".to_owned())), 2),
+                ((1.0, OwnedValue::Str("greenville".to_owned())), 1),
+                ((1.0, OwnedValue::Str("austin".to_owned())), 0),
+                ((1.0, OwnedValue::Null), 3),
+            ]
+        );
+        Ok(())
+    }
+
     use proptest::prelude::*;
 
     proptest! {

src/collector/sort_key/order.rs

@@ -1,11 +1,70 @@
 use std::cmp::Ordering;
 
+use columnar::MonotonicallyMappableToU64;
 use serde::{Deserialize, Serialize};
 
 use crate::collector::{SegmentSortKeyComputer, SortKeyComputer};
-use crate::schema::Schema;
+use crate::schema::{OwnedValue, Schema};
 use crate::{DocId, Order, Score};
 
+fn compare_owned_value<const NULLS_FIRST: bool>(lhs: &OwnedValue, rhs: &OwnedValue) -> Ordering {
+    match (lhs, rhs) {
+        (OwnedValue::Null, OwnedValue::Null) => Ordering::Equal,
+        (OwnedValue::Null, _) => {
+            if NULLS_FIRST {
+                Ordering::Less
+            } else {
+                Ordering::Greater
+            }
+        }
+        (_, OwnedValue::Null) => {
+            if NULLS_FIRST {
+                Ordering::Greater
+            } else {
+                Ordering::Less
+            }
+        }
+        (OwnedValue::Str(a), OwnedValue::Str(b)) => a.cmp(b),
+        (OwnedValue::PreTokStr(a), OwnedValue::PreTokStr(b)) => a.cmp(b),
+        (OwnedValue::U64(a), OwnedValue::U64(b)) => a.cmp(b),
+        (OwnedValue::I64(a), OwnedValue::I64(b)) => a.cmp(b),
+        (OwnedValue::F64(a), OwnedValue::F64(b)) => a.to_u64().cmp(&b.to_u64()),
+        (OwnedValue::Bool(a), OwnedValue::Bool(b)) => a.cmp(b),
+        (OwnedValue::Date(a), OwnedValue::Date(b)) => a.cmp(b),
+        (OwnedValue::Facet(a), OwnedValue::Facet(b)) => a.cmp(b),
+        (OwnedValue::Bytes(a), OwnedValue::Bytes(b)) => a.cmp(b),
+        (OwnedValue::IpAddr(a), OwnedValue::IpAddr(b)) => a.cmp(b),
+        (OwnedValue::U64(a), OwnedValue::I64(b)) => {
+            if *b < 0 {
+                Ordering::Greater
+            } else {
+                a.cmp(&(*b as u64))
+            }
+        }
+        (OwnedValue::I64(a), OwnedValue::U64(b)) => {
+            if *a < 0 {
+                Ordering::Less
+            } else {
+                (*a as u64).cmp(b)
+            }
+        }
+        (OwnedValue::U64(a), OwnedValue::F64(b)) => (*a as f64).to_u64().cmp(&b.to_u64()),
+        (OwnedValue::F64(a), OwnedValue::U64(b)) => a.to_u64().cmp(&(*b as f64).to_u64()),
+        (OwnedValue::I64(a), OwnedValue::F64(b)) => (*a as f64).to_u64().cmp(&b.to_u64()),
+        (OwnedValue::F64(a), OwnedValue::I64(b)) => a.to_u64().cmp(&(*b as f64).to_u64()),
+        (a, b) => {
+            let ord = a.discriminant_value().cmp(&b.discriminant_value());
+            // If the discriminant is equal, it's because a new type was added, but hasn't been
+            // included in this `match` statement.
+            assert!(
+                ord != Ordering::Equal,
+                "Unimplemented comparison for type of {a:?}, {b:?}"
+            );
+            ord
+        }
+    }
+}
+
 /// Comparator trait defining the order in which documents should be ordered.
 pub trait Comparator<T>: Send + Sync + std::fmt::Debug + Default {
     /// Return the order between two values.
@@ -25,7 +84,18 @@ pub struct NaturalComparator;
 impl<T: PartialOrd> Comparator<T> for NaturalComparator {
     #[inline(always)]
     fn compare(&self, lhs: &T, rhs: &T) -> Ordering {
-        lhs.partial_cmp(rhs).unwrap()
+        lhs.partial_cmp(rhs).unwrap_or(Ordering::Equal)
+    }
+}
+
+/// A (partial) implementation of comparison for OwnedValue.
+///
+/// Intended for use within columns of homogenous types, and so will panic for OwnedValues with
+/// mismatched types. The one exception is Null, for which we do define all comparisons.
+impl Comparator<OwnedValue> for NaturalComparator {
+    #[inline(always)]
+    fn compare(&self, lhs: &OwnedValue, rhs: &OwnedValue) -> Ordering {
+        compare_owned_value::</* NULLS_FIRST= */ true>(lhs, rhs)
     }
 }
 
@@ -121,6 +191,13 @@ impl Comparator<String> for ReverseNoneIsLowerComparator {
     }
 }
 
+impl Comparator<OwnedValue> for ReverseNoneIsLowerComparator {
+    #[inline(always)]
+    fn compare(&self, lhs: &OwnedValue, rhs: &OwnedValue) -> Ordering {
+        compare_owned_value::</* NULLS_FIRST= */ false>(rhs, lhs)
+    }
+}
+
 /// Compare values naturally, but treating `None` as higher than `Some`.
 ///
 /// When used with `TopDocs`, which reverses the order, this results in a
@@ -185,6 +262,13 @@ impl Comparator<String> for NaturalNoneIsHigherComparator {
     }
 }
 
+impl Comparator<OwnedValue> for NaturalNoneIsHigherComparator {
+    #[inline(always)]
+    fn compare(&self, lhs: &OwnedValue, rhs: &OwnedValue) -> Ordering {
+        compare_owned_value::</* NULLS_FIRST= */ false>(lhs, rhs)
+    }
+}
+
 /// An enum representing the different sort orders.
 #[derive(Debug, Clone, Copy, Eq, PartialEq, Default)]
 pub enum ComparatorEnum {
@@ -404,11 +488,12 @@ impl<TSegmentSortKeyComputer, TSegmentSortKey, TComparator> SegmentSortKeyComput
     for SegmentSortKeyComputerWithComparator<TSegmentSortKeyComputer, TComparator>
 where
     TSegmentSortKeyComputer: SegmentSortKeyComputer<SegmentSortKey = TSegmentSortKey>,
-    TSegmentSortKey: PartialOrd + Clone + 'static + Sync + Send,
+    TSegmentSortKey: Clone + 'static + Sync + Send,
     TComparator: Comparator<TSegmentSortKey> + 'static + Sync + Send,
 {
     type SortKey = TSegmentSortKeyComputer::SortKey;
     type SegmentSortKey = TSegmentSortKey;
+    type SegmentComparator = TComparator;
 
     fn segment_sort_key(&mut self, doc: DocId, score: Score) -> Self::SegmentSortKey {
         self.segment_sort_key_computer.segment_sort_key(doc, score)
@@ -432,6 +517,7 @@ where
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::schema::OwnedValue;
 
     #[test]
     fn test_natural_none_is_higher() {
@@ -455,4 +541,27 @@ mod tests {
         // compare(None, None) should be Equal.
         assert_eq!(comp.compare(&null, &null), Ordering::Equal);
     }
+
+    #[test]
+    fn test_mixed_ownedvalue_compare() {
+        let u = OwnedValue::U64(10);
+        let i = OwnedValue::I64(10);
+        let f = OwnedValue::F64(10.0);
+
+        let nc = NaturalComparator;
+        assert_eq!(nc.compare(&u, &i), Ordering::Equal);
+        assert_eq!(nc.compare(&u, &f), Ordering::Equal);
+        assert_eq!(nc.compare(&i, &f), Ordering::Equal);
+
+        let u2 = OwnedValue::U64(11);
+        assert_eq!(nc.compare(&u2, &f), Ordering::Greater);
+
+        let s = OwnedValue::Str("a".to_string());
+        // Str < U64
+        assert_eq!(nc.compare(&s, &u), Ordering::Less);
+        // Str < I64
+        assert_eq!(nc.compare(&s, &i), Ordering::Less);
+        // Str < F64
+        assert_eq!(nc.compare(&s, &f), Ordering::Less);
+    }
 }

src/collector/sort_key/sort_by_erased_type.rs

@@ -0,0 +1,361 @@
+use columnar::{ColumnType, MonotonicallyMappableToU64};
+
+use crate::collector::sort_key::{
+    NaturalComparator, SortBySimilarityScore, SortByStaticFastValue, SortByString,
+};
+use crate::collector::{SegmentSortKeyComputer, SortKeyComputer};
+use crate::fastfield::FastFieldNotAvailableError;
+use crate::schema::OwnedValue;
+use crate::{DateTime, DocId, Score};
+
+/// Sort by the boxed / OwnedValue representation of either a fast field, or of the score.
+///
+/// Using the OwnedValue representation allows for type erasure, and can be useful when sort orders
+/// are not known until runtime. But it comes with a performance cost: wherever possible, prefer to
+/// use a SortKeyComputer implementation with a known-type at compile time.
+#[derive(Debug, Clone)]
+pub enum SortByErasedType {
+    /// Sort by a fast field
+    Field(String),
+    /// Sort by score
+    Score,
+}
+
+impl SortByErasedType {
+    /// Creates a new sort key computer which will sort by the given fast field column, with type
+    /// erasure.
+    pub fn for_field(column_name: impl ToString) -> Self {
+        Self::Field(column_name.to_string())
+    }
+
+    /// Creates a new sort key computer which will sort by score, with type erasure.
+    pub fn for_score() -> Self {
+        Self::Score
+    }
+}
+
+trait ErasedSegmentSortKeyComputer: Send + Sync {
+    fn segment_sort_key(&mut self, doc: DocId, score: Score) -> Option<u64>;
+    fn convert_segment_sort_key(&self, sort_key: Option<u64>) -> OwnedValue;
+}
+
+struct ErasedSegmentSortKeyComputerWrapper<C, F> {
+    inner: C,
+    converter: F,
+}
+
+impl<C, F> ErasedSegmentSortKeyComputer for ErasedSegmentSortKeyComputerWrapper<C, F>
+where
+    C: SegmentSortKeyComputer<SegmentSortKey = Option<u64>> + Send + Sync,
+    F: Fn(C::SortKey) -> OwnedValue + Send + Sync + 'static,
+{
+    fn segment_sort_key(&mut self, doc: DocId, score: Score) -> Option<u64> {
+        self.inner.segment_sort_key(doc, score)
+    }
+
+    fn convert_segment_sort_key(&self, sort_key: Option<u64>) -> OwnedValue {
+        let val = self.inner.convert_segment_sort_key(sort_key);
+        (self.converter)(val)
+    }
+}
+
+struct ScoreSegmentSortKeyComputer {
+    segment_computer: SortBySimilarityScore,
+}
+
+impl ErasedSegmentSortKeyComputer for ScoreSegmentSortKeyComputer {
+    fn segment_sort_key(&mut self, doc: DocId, score: Score) -> Option<u64> {
+        let score_value: f64 = self.segment_computer.segment_sort_key(doc, score).into();
+        Some(score_value.to_u64())
+    }
+
+    fn convert_segment_sort_key(&self, sort_key: Option<u64>) -> OwnedValue {
+        let score_value: u64 = sort_key.expect("This implementation always produces a score.");
+        OwnedValue::F64(f64::from_u64(score_value))
+    }
+}
+
+impl SortKeyComputer for SortByErasedType {
+    type SortKey = OwnedValue;
+    type Child = ErasedColumnSegmentSortKeyComputer;
+    type Comparator = NaturalComparator;
+
+    fn requires_scoring(&self) -> bool {
+        matches!(self, Self::Score)
+    }
+
+    fn segment_sort_key_computer(
+        &self,
+        segment_reader: &crate::SegmentReader,
+    ) -> crate::Result<Self::Child> {
+        let inner: Box<dyn ErasedSegmentSortKeyComputer> = match self {
+            Self::Field(column_name) => {
+                let fast_fields = segment_reader.fast_fields();
+                // TODO: We currently double-open the column to avoid relying on the implementation
+                // details of `SortByString` or `SortByStaticFastValue`. Once
+                // https://github.com/quickwit-oss/tantivy/issues/2776 is resolved, we should
+                // consider directly constructing the appropriate `SegmentSortKeyComputer` type for
+                // the column that we open here.
+                let (_column, column_type) =
+                    fast_fields.u64_lenient(column_name)?.ok_or_else(|| {
+                        FastFieldNotAvailableError {
+                            field_name: column_name.to_owned(),
+                        }
+                    })?;
+
+                match column_type {
+                    ColumnType::Str => {
+                        let computer = SortByString::for_field(column_name);
+                        let inner = computer.segment_sort_key_computer(segment_reader)?;
+                        Box::new(ErasedSegmentSortKeyComputerWrapper {
+                            inner,
+                            converter: |val: Option<String>| {
+                                val.map(OwnedValue::Str).unwrap_or(OwnedValue::Null)
+                            },
+                        })
+                    }
+                    ColumnType::U64 => {
+                        let computer = SortByStaticFastValue::<u64>::for_field(column_name);
+                        let inner = computer.segment_sort_key_computer(segment_reader)?;
+                        Box::new(ErasedSegmentSortKeyComputerWrapper {
+                            inner,
+                            converter: |val: Option<u64>| {
+                                val.map(OwnedValue::U64).unwrap_or(OwnedValue::Null)
+                            },
+                        })
+                    }
+                    ColumnType::I64 => {
+                        let computer = SortByStaticFastValue::<i64>::for_field(column_name);
+                        let inner = computer.segment_sort_key_computer(segment_reader)?;
+                        Box::new(ErasedSegmentSortKeyComputerWrapper {
+                            inner,
+                            converter: |val: Option<i64>| {
+                                val.map(OwnedValue::I64).unwrap_or(OwnedValue::Null)
+                            },
+                        })
+                    }
+                    ColumnType::F64 => {
+                        let computer = SortByStaticFastValue::<f64>::for_field(column_name);
+                        let inner = computer.segment_sort_key_computer(segment_reader)?;
+                        Box::new(ErasedSegmentSortKeyComputerWrapper {
+                            inner,
+                            converter: |val: Option<f64>| {
+                                val.map(OwnedValue::F64).unwrap_or(OwnedValue::Null)
+                            },
+                        })
+                    }
+                    ColumnType::Bool => {
+                        let computer = SortByStaticFastValue::<bool>::for_field(column_name);
+                        let inner = computer.segment_sort_key_computer(segment_reader)?;
+                        Box::new(ErasedSegmentSortKeyComputerWrapper {
+                            inner,
+                            converter: |val: Option<bool>| {
+                                val.map(OwnedValue::Bool).unwrap_or(OwnedValue::Null)
+                            },
+                        })
+                    }
+                    ColumnType::DateTime => {
+                        let computer = SortByStaticFastValue::<DateTime>::for_field(column_name);
+                        let inner = computer.segment_sort_key_computer(segment_reader)?;
+                        Box::new(ErasedSegmentSortKeyComputerWrapper {
+                            inner,
+                            converter: |val: Option<DateTime>| {
+                                val.map(OwnedValue::Date).unwrap_or(OwnedValue::Null)
+                            },
+                        })
+                    }
+                    column_type => {
+                        return Err(crate::TantivyError::SchemaError(format!(
+                            "Field `{}` is of type {column_type:?}, which is not supported for \
+                             sorting by owned value yet.",
+                            column_name
+                        )))
+                    }
+                }
+            }
+            Self::Score => Box::new(ScoreSegmentSortKeyComputer {
+                segment_computer: SortBySimilarityScore,
+            }),
+        };
+        Ok(ErasedColumnSegmentSortKeyComputer { inner })
+    }
+}
+
+pub struct ErasedColumnSegmentSortKeyComputer {
+    inner: Box<dyn ErasedSegmentSortKeyComputer>,
+}
+
+impl SegmentSortKeyComputer for ErasedColumnSegmentSortKeyComputer {
+    type SortKey = OwnedValue;
+    type SegmentSortKey = Option<u64>;
+    type SegmentComparator = NaturalComparator;
+
+    #[inline(always)]
+    fn segment_sort_key(&mut self, doc: DocId, score: Score) -> Option<u64> {
+        self.inner.segment_sort_key(doc, score)
+    }
+
+    fn convert_segment_sort_key(&self, segment_sort_key: Self::SegmentSortKey) -> OwnedValue {
+        self.inner.convert_segment_sort_key(segment_sort_key)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::collector::sort_key::{ComparatorEnum, SortByErasedType};
+    use crate::collector::TopDocs;
+    use crate::query::AllQuery;
+    use crate::schema::{OwnedValue, Schema, FAST, TEXT};
+    use crate::Index;
+
+    #[test]
+    fn test_sort_by_owned_u64() {
+        let mut schema_builder = Schema::builder();
+        let id_field = schema_builder.add_u64_field("id", FAST);
+        let schema = schema_builder.build();
+        let index = Index::create_in_ram(schema);
+        let mut writer = index.writer_for_tests().unwrap();
+        writer.add_document(doc!(id_field => 10u64)).unwrap();
+        writer.add_document(doc!(id_field => 2u64)).unwrap();
+        writer.add_document(doc!()).unwrap();
+        writer.commit().unwrap();
+
+        let reader = index.reader().unwrap();
+        let searcher = reader.searcher();
+
+        let collector = TopDocs::with_limit(10)
+            .order_by((SortByErasedType::for_field("id"), ComparatorEnum::Natural));
+        let top_docs = searcher.search(&AllQuery, &collector).unwrap();
+
+        let values: Vec<OwnedValue> = top_docs.into_iter().map(|(key, _)| key).collect();
+
+        assert_eq!(
+            values,
+            vec![OwnedValue::U64(10), OwnedValue::U64(2), OwnedValue::Null]
+        );
+
+        let collector = TopDocs::with_limit(10).order_by((
+            SortByErasedType::for_field("id"),
+            ComparatorEnum::ReverseNoneLower,
+        ));
+        let top_docs = searcher.search(&AllQuery, &collector).unwrap();
+
+        let values: Vec<OwnedValue> = top_docs.into_iter().map(|(key, _)| key).collect();
+
+        assert_eq!(
+            values,
+            vec![OwnedValue::U64(2), OwnedValue::U64(10), OwnedValue::Null]
+        );
+    }
+
+    #[test]
+    fn test_sort_by_owned_string() {
+        let mut schema_builder = Schema::builder();
+        let city_field = schema_builder.add_text_field("city", FAST | TEXT);
+        let schema = schema_builder.build();
+        let index = Index::create_in_ram(schema);
+        let mut writer = index.writer_for_tests().unwrap();
+        writer.add_document(doc!(city_field => "tokyo")).unwrap();
+        writer.add_document(doc!(city_field => "austin")).unwrap();
+        writer.add_document(doc!()).unwrap();
+        writer.commit().unwrap();
+
+        let reader = index.reader().unwrap();
+        let searcher = reader.searcher();
+
+        let collector = TopDocs::with_limit(10).order_by((
+            SortByErasedType::for_field("city"),
+            ComparatorEnum::ReverseNoneLower,
+        ));
+        let top_docs = searcher.search(&AllQuery, &collector).unwrap();
+
+        let values: Vec<OwnedValue> = top_docs.into_iter().map(|(key, _)| key).collect();
+
+        assert_eq!(
+            values,
+            vec![
+                OwnedValue::Str("austin".to_string()),
+                OwnedValue::Str("tokyo".to_string()),
+                OwnedValue::Null
+            ]
+        );
+    }
+
+    #[test]
+    fn test_sort_by_owned_reverse() {
+        let mut schema_builder = Schema::builder();
+        let id_field = schema_builder.add_u64_field("id", FAST);
+        let schema = schema_builder.build();
+        let index = Index::create_in_ram(schema);
+        let mut writer = index.writer_for_tests().unwrap();
+        writer.add_document(doc!(id_field => 10u64)).unwrap();
+        writer.add_document(doc!(id_field => 2u64)).unwrap();
+        writer.add_document(doc!()).unwrap();
+        writer.commit().unwrap();
+
+        let reader = index.reader().unwrap();
+        let searcher = reader.searcher();
+
+        let collector = TopDocs::with_limit(10)
+            .order_by((SortByErasedType::for_field("id"), ComparatorEnum::Reverse));
+        let top_docs = searcher.search(&AllQuery, &collector).unwrap();
+
+        let values: Vec<OwnedValue> = top_docs.into_iter().map(|(key, _)| key).collect();
+
+        assert_eq!(
+            values,
+            vec![OwnedValue::Null, OwnedValue::U64(2), OwnedValue::U64(10)]
+        );
+    }
+
+    #[test]
+    fn test_sort_by_owned_score() {
+        let mut schema_builder = Schema::builder();
+        let body_field = schema_builder.add_text_field("body", TEXT);
+        let schema = schema_builder.build();
+        let index = Index::create_in_ram(schema);
+        let mut writer = index.writer_for_tests().unwrap();
+        writer.add_document(doc!(body_field => "a a")).unwrap();
+        writer.add_document(doc!(body_field => "a")).unwrap();
+        writer.commit().unwrap();
+
+        let reader = index.reader().unwrap();
+        let searcher = reader.searcher();
+        let query_parser = crate::query::QueryParser::for_index(&index, vec![body_field]);
+        let query = query_parser.parse_query("a").unwrap();
+
+        // Sort by score descending (Natural)
+        let collector = TopDocs::with_limit(10)
+            .order_by((SortByErasedType::for_score(), ComparatorEnum::Natural));
+        let top_docs = searcher.search(&query, &collector).unwrap();
+
+        let values: Vec<f64> = top_docs
+            .into_iter()
+            .map(|(key, _)| match key {
+                OwnedValue::F64(val) => val,
+                _ => panic!("Wrong type {key:?}"),
+            })
+            .collect();
+
+        assert_eq!(values.len(), 2);
+        assert!(values[0] > values[1]);
+
+        // Sort by score ascending (ReverseNoneLower)
+        let collector = TopDocs::with_limit(10).order_by((
+            SortByErasedType::for_score(),
+            ComparatorEnum::ReverseNoneLower,
+        ));
+        let top_docs = searcher.search(&query, &collector).unwrap();
+
+        let values: Vec<f64> = top_docs
+            .into_iter()
+            .map(|(key, _)| match key {
+                OwnedValue::F64(val) => val,
+                _ => panic!("Wrong type {key:?}"),
+            })
+            .collect();
+
+        assert_eq!(values.len(), 2);
+        assert!(values[0] < values[1]);
+    }
+}

src/collector/sort_key/sort_by_score.rs

@@ -63,8 +63,8 @@ impl SortKeyComputer for SortBySimilarityScore {
 
 impl SegmentSortKeyComputer for SortBySimilarityScore {
     type SortKey = Score;
-
     type SegmentSortKey = Score;
+    type SegmentComparator = NaturalComparator;
 
     #[inline(always)]
     fn segment_sort_key(&mut self, _doc: DocId, score: Score) -> Score {

src/collector/sort_key/sort_by_static_fast_value.rs

@@ -34,9 +34,7 @@ impl<T: FastValue> SortByStaticFastValue<T> {
 
 impl<T: FastValue> SortKeyComputer for SortByStaticFastValue<T> {
     type Child = SortByFastValueSegmentSortKeyComputer<T>;
-
     type SortKey = Option<T>;
-
     type Comparator = NaturalComparator;
 
     fn check_schema(&self, schema: &crate::schema::Schema) -> crate::Result<()> {
@@ -84,8 +82,8 @@ pub struct SortByFastValueSegmentSortKeyComputer<T> {
 
 impl<T: FastValue> SegmentSortKeyComputer for SortByFastValueSegmentSortKeyComputer<T> {
     type SortKey = Option<T>;
-
     type SegmentSortKey = Option<u64>;
+    type SegmentComparator = NaturalComparator;
 
     #[inline(always)]
     fn segment_sort_key(&mut self, doc: DocId, _score: Score) -> Self::SegmentSortKey {

src/collector/sort_key/sort_by_string.rs

@@ -30,9 +30,7 @@ impl SortByString {
 
 impl SortKeyComputer for SortByString {
     type SortKey = Option<String>;
-
     type Child = ByStringColumnSegmentSortKeyComputer;
-
     type Comparator = NaturalComparator;
 
     fn segment_sort_key_computer(
@@ -50,8 +48,8 @@ pub struct ByStringColumnSegmentSortKeyComputer {
 
 impl SegmentSortKeyComputer for ByStringColumnSegmentSortKeyComputer {
     type SortKey = Option<String>;
-
     type SegmentSortKey = Option<TermOrdinal>;
+    type SegmentComparator = NaturalComparator;
 
     #[inline(always)]
     fn segment_sort_key(&mut self, doc: DocId, _score: Score) -> Option<TermOrdinal> {
@@ -60,6 +58,8 @@ impl SegmentSortKeyComputer for ByStringColumnSegmentSortKeyComputer {
     }
 
     fn convert_segment_sort_key(&self, term_ord_opt: Option<TermOrdinal>) -> Option<String> {
+        // TODO: Individual lookups to the dictionary like this are very likely to repeatedly
+        // decompress the same blocks. See https://github.com/quickwit-oss/tantivy/issues/2776
         let term_ord = term_ord_opt?;
         let str_column = self.str_column_opt.as_ref()?;
         let mut bytes = Vec::new();

src/collector/sort_key/sort_key_computer.rs

@@ -12,13 +12,21 @@ use crate::{DocAddress, DocId, Result, Score, SegmentReader};
 /// It is the segment local version of the [`SortKeyComputer`].
 pub trait SegmentSortKeyComputer: 'static {
     /// The final score being emitted.
-    type SortKey: 'static + PartialOrd + Send + Sync + Clone;
+    type SortKey: 'static + Send + Sync + Clone;
 
     /// Sort key used by at the segment level by the `SegmentSortKeyComputer`.
     ///
     /// It is typically small like a `u64`, and is meant to be converted
     /// to the final score at the end of the collection of the segment.
-    type SegmentSortKey: 'static + PartialOrd + Clone + Send + Sync + Clone;
+    type SegmentSortKey: 'static + Clone + Send + Sync + Clone;
+
+    /// Comparator type.
+    type SegmentComparator: Comparator<Self::SegmentSortKey> + 'static;
+
+    /// Returns the segment sort key comparator.
+    fn segment_comparator(&self) -> Self::SegmentComparator {
+        Self::SegmentComparator::default()
+    }
 
     /// Computes the sort key for the given document and score.
     fn segment_sort_key(&mut self, doc: DocId, score: Score) -> Self::SegmentSortKey;
@@ -47,7 +55,7 @@ pub trait SegmentSortKeyComputer: 'static {
         left: &Self::SegmentSortKey,
         right: &Self::SegmentSortKey,
     ) -> Ordering {
-        NaturalComparator.compare(left, right)
+        self.segment_comparator().compare(left, right)
     }
 
     /// Implementing this method makes it possible to avoid computing
@@ -81,7 +89,7 @@ pub trait SegmentSortKeyComputer: 'static {
 /// the sort key at a segment scale.
 pub trait SortKeyComputer: Sync {
     /// The sort key type.
-    type SortKey: 'static + Send + Sync + PartialOrd + Clone + std::fmt::Debug;
+    type SortKey: 'static + Send + Sync + Clone + std::fmt::Debug;
     /// Type of the associated [`SegmentSortKeyComputer`].
     type Child: SegmentSortKeyComputer<SortKey = Self::SortKey>;
     /// Comparator type.
@@ -136,10 +144,7 @@ where
     HeadSortKeyComputer: SortKeyComputer,
     TailSortKeyComputer: SortKeyComputer,
 {
-    type SortKey = (
+    type SortKey = (HeadSortKeyComputer::SortKey, TailSortKeyComputer::SortKey);
-        <HeadSortKeyComputer::Child as SegmentSortKeyComputer>::SortKey,
-        <TailSortKeyComputer::Child as SegmentSortKeyComputer>::SortKey,
-    );
     type Child = (HeadSortKeyComputer::Child, TailSortKeyComputer::Child);
 
     type Comparator = (
@@ -188,6 +193,11 @@ where
         TailSegmentSortKeyComputer::SegmentSortKey,
     );
 
+    type SegmentComparator = (
+        HeadSegmentSortKeyComputer::SegmentComparator,
+        TailSegmentSortKeyComputer::SegmentComparator,
+    );
+
     /// A SegmentSortKeyComputer maps to a SegmentSortKey, but it can also decide on
     /// its ordering.
     ///
@@ -269,11 +279,12 @@ impl<T, PreviousScore, NewScore> SegmentSortKeyComputer
     for MappedSegmentSortKeyComputer<T, PreviousScore, NewScore>
 where
     T: SegmentSortKeyComputer<SortKey = PreviousScore>,
-    PreviousScore: 'static + Clone + Send + Sync + PartialOrd,
+    PreviousScore: 'static + Clone + Send + Sync,
-    NewScore: 'static + Clone + Send + Sync + PartialOrd,
+    NewScore: 'static + Clone + Send + Sync,
 {
     type SortKey = NewScore;
     type SegmentSortKey = T::SegmentSortKey;
+    type SegmentComparator = T::SegmentComparator;
 
     fn segment_sort_key(&mut self, doc: DocId, score: Score) -> Self::SegmentSortKey {
         self.sort_key_computer.segment_sort_key(doc, score)
@@ -463,6 +474,7 @@ where
 {
     type SortKey = TSortKey;
     type SegmentSortKey = TSortKey;
+    type SegmentComparator = NaturalComparator;
 
     fn segment_sort_key(&mut self, doc: DocId, _score: Score) -> TSortKey {
         (self)(doc)

src/collector/top_score_collector.rs

@@ -324,7 +324,7 @@ impl TopDocs {
         sort_key_computer: impl SortKeyComputer<SortKey = TSortKey> + Send + 'static,
     ) -> impl Collector<Fruit = Vec<(TSortKey, DocAddress)>>
     where
-        TSortKey: 'static + Clone + Send + Sync + PartialOrd + std::fmt::Debug,
+        TSortKey: 'static + Clone + Send + Sync + std::fmt::Debug,
     {
         TopBySortKeyCollector::new(sort_key_computer, self.doc_range())
     }
@@ -445,7 +445,7 @@ where
     F: 'static + Send + Sync + Fn(&SegmentReader) -> TTweakScoreSortKeyFn,
     TTweakScoreSortKeyFn: 'static + Fn(DocId, Score) -> TSortKey,
     TweakScoreSegmentSortKeyComputer<TTweakScoreSortKeyFn>:
-        SegmentSortKeyComputer<SortKey = TSortKey>,
+        SegmentSortKeyComputer<SortKey = TSortKey, SegmentSortKey = TSortKey>,
     TSortKey: 'static + PartialOrd + Clone + Send + Sync + std::fmt::Debug,
 {
     type SortKey = TSortKey;
@@ -480,6 +480,7 @@ where
 {
     type SortKey = TSortKey;
     type SegmentSortKey = TSortKey;
+    type SegmentComparator = NaturalComparator;
 
     fn segment_sort_key(&mut self, doc: DocId, score: Score) -> TSortKey {
         (self.sort_key_fn)(doc, score)

src/core/executor.rs

@@ -48,7 +48,15 @@ impl Executor {
         F: Sized + Sync + Fn(A) -> crate::Result<R>,
     {
         match self {
-            Executor::SingleThread => args.map(f).collect::<crate::Result<_>>(),
+            Executor::SingleThread => {
+                // Avoid `collect`, since the stacktrace is blown up by it, which makes profiling
+                // harder.
+                let mut result = Vec::with_capacity(args.size_hint().0);
+                for arg in args {
+                    result.push(f(arg)?);
+                }
+                Ok(result)
+            }
             Executor::ThreadPool(pool) => {
                 let args: Vec<A> = args.collect();
                 let num_fruits = args.len();

src/directory/mmap_directory/mod.rs

@@ -1,3 +1,5 @@
+mod file_watcher;
+
 use std::collections::HashMap;
 use std::fmt;
 use std::fs::{self, File, OpenOptions};
@@ -7,6 +9,7 @@ use std::path::{Path, PathBuf};
 use std::sync::{Arc, RwLock, Weak};
 
 use common::StableDeref;
+use file_watcher::FileWatcher;
 use fs4::fs_std::FileExt;
 #[cfg(all(feature = "mmap", unix))]
 pub use memmap2::Advice;
@@ -18,7 +21,6 @@ use crate::core::META_FILEPATH;
 use crate::directory::error::{
     DeleteError, LockError, OpenDirectoryError, OpenReadError, OpenWriteError,
 };
-use crate::directory::file_watcher::FileWatcher;
 use crate::directory::{
     AntiCallToken, Directory, DirectoryLock, FileHandle, Lock, OwnedBytes, TerminatingWrite,
     WatchCallback, WatchHandle, WritePtr,

src/directory/mod.rs

@@ -5,7 +5,6 @@ mod mmap_directory;
 
 mod directory;
 mod directory_lock;
-mod file_watcher;
 pub mod footer;
 mod managed_directory;
 mod ram_directory;

src/docset.rs

@@ -42,7 +42,6 @@ pub trait DocSet: Send {
     /// Calling `seek(TERMINATED)` is also legal and is the normal way to consume a `DocSet`.
     ///
     /// `target` has to be larger or equal to `.doc()` when calling `seek`.
-    /// If `target` is equal to `.doc()` then the DocSet should not advance.
     fn seek(&mut self, target: DocId) -> DocId {
         let mut doc = self.doc();
         debug_assert!(doc <= target);
@@ -167,19 +166,6 @@ pub trait DocSet: Send {
     }
 }
 
-/// Consumes the `DocSet` and returns a Vec with all of the docs in the DocSet
-/// including the current doc.
-#[cfg(test)]
-pub fn docset_to_doc_vec(mut doc_set: Box<dyn DocSet>) -> Vec<DocId> {
-    let mut output = Vec::new();
-    let mut doc = doc_set.doc();
-    while doc != TERMINATED {
-        output.push(doc);
-        doc = doc_set.advance();
-    }
-    output
-}
-
 impl DocSet for &mut dyn DocSet {
     fn advance(&mut self) -> u32 {
         (**self).advance()

src/fieldnorm/mod.rs

@@ -113,7 +113,7 @@ mod tests {
             IndexRecordOption::WithFreqs,
         );
         let weight = query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
-        let mut scorer = weight.scorer(searcher.segment_reader(0), 1.0f32, 0)?;
+        let mut scorer = weight.scorer(searcher.segment_reader(0), 1.0f32)?;
         assert_eq!(scorer.doc(), 0);
         assert!((scorer.score() - 0.22920431).abs() < 0.001f32);
         assert_eq!(scorer.advance(), 1);
@@ -142,7 +142,7 @@ mod tests {
             IndexRecordOption::WithFreqs,
         );
         let weight = query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
-        let mut scorer = weight.scorer(searcher.segment_reader(0), 1.0f32, 0)?;
+        let mut scorer = weight.scorer(searcher.segment_reader(0), 1.0f32)?;
         assert_eq!(scorer.doc(), 0);
         assert!((scorer.score() - 0.22920431).abs() < 0.001f32);
         assert_eq!(scorer.advance(), 1);

src/index/index_meta.rs

@@ -404,7 +404,10 @@ mod tests {
             schema_builder.build()
         };
         let index_metas = IndexMeta {
-            index_settings: IndexSettings::default(),
+            index_settings: IndexSettings {
+                docstore_compression: Compressor::None,
+                ..Default::default()
+            },
             segments: Vec::new(),
             schema,
             opstamp: 0u64,
@@ -413,7 +416,7 @@ mod tests {
         let json = serde_json::ser::to_string(&index_metas).expect("serialization failed");
         assert_eq!(
             json,
-            r#"{"index_settings":{"docstore_compression":"lz4","docstore_blocksize":16384},"segments":[],"schema":[{"name":"text","type":"text","options":{"indexing":{"record":"position","fieldnorms":true,"tokenizer":"default"},"stored":false,"fast":false}}],"opstamp":0}"#
+            r#"{"index_settings":{"docstore_compression":"none","docstore_blocksize":16384},"segments":[],"schema":[{"name":"text","type":"text","options":{"indexing":{"record":"position","fieldnorms":true,"tokenizer":"default"},"stored":false,"fast":false}}],"opstamp":0}"#
         );
 
         let deser_meta: UntrackedIndexMeta = serde_json::from_str(&json).unwrap();
@@ -494,6 +497,8 @@ mod tests {
     #[test]
     #[cfg(feature = "lz4-compression")]
     fn test_index_settings_default() {
+        use crate::store::Compressor;
+
         let mut index_settings = IndexSettings::default();
         assert_eq!(
             index_settings,

src/index/inverted_index_reader.rs

@@ -14,7 +14,6 @@ use crate::positions::PositionReader;
 use crate::postings::{BlockSegmentPostings, SegmentPostings, TermInfo};
 use crate::schema::{IndexRecordOption, Term, Type};
 use crate::termdict::TermDictionary;
-use crate::DocId;
 
 /// The inverted index reader is in charge of accessing
 /// the inverted index associated with a specific field.
@@ -193,34 +192,9 @@ impl InvertedIndexReader {
         term: &Term,
         option: IndexRecordOption,
     ) -> io::Result<Option<BlockSegmentPostings>> {
-        let Some(term_info) = self.get_term_info(term)? else {
+        self.get_term_info(term)?
-            return Ok(None);
+            .map(move |term_info| self.read_block_postings_from_terminfo(&term_info, option))
-        };
+            .transpose()
-        let block_postings_not_loaded =
-            self.read_block_postings_from_terminfo(&term_info, option)?;
-        Ok(Some(block_postings_not_loaded))
-    }
-
-    /// Returns a block postings given a `term_info`.
-    /// This method is for an advanced usage only.
-    ///
-    /// Most users should prefer using [`Self::read_postings()`] instead.
-    pub(crate) fn read_block_postings_from_terminfo_with_seek(
-        &self,
-        term_info: &TermInfo,
-        requested_option: IndexRecordOption,
-        seek_doc: DocId,
-    ) -> io::Result<(BlockSegmentPostings, usize)> {
-        let postings_data = self
-            .postings_file_slice
-            .slice(term_info.postings_range.clone());
-        BlockSegmentPostings::open(
-            term_info.doc_freq,
-            postings_data,
-            self.record_option,
-            requested_option,
-            seek_doc,
-        )
     }
 
     /// Returns a block postings given a `term_info`.
@@ -232,9 +206,15 @@ impl InvertedIndexReader {
         term_info: &TermInfo,
         requested_option: IndexRecordOption,
     ) -> io::Result<BlockSegmentPostings> {
-        let (block_segment_postings, _) =
+        let postings_data = self
-            self.read_block_postings_from_terminfo_with_seek(term_info, requested_option, 0)?;
+            .postings_file_slice
-        Ok(block_segment_postings)
+            .slice(term_info.postings_range.clone());
+        BlockSegmentPostings::open(
+            term_info.doc_freq,
+            postings_data,
+            self.record_option,
+            requested_option,
+        )
     }
 
     /// Returns a posting object given a `term_info`.
@@ -244,13 +224,13 @@ impl InvertedIndexReader {
     pub fn read_postings_from_terminfo(
         &self,
         term_info: &TermInfo,
-        record_option: IndexRecordOption,
+        option: IndexRecordOption,
-        seek_doc: DocId,
     ) -> io::Result<SegmentPostings> {
-        let (block_segment_postings, position_within_block) =
+        let option = option.downgrade(self.record_option);
-            self.read_block_postings_from_terminfo_with_seek(term_info, record_option, seek_doc)?;
+
+        let block_postings = self.read_block_postings_from_terminfo(term_info, option)?;
         let position_reader = {
-            if record_option.has_positions() {
+            if option.has_positions() {
                 let positions_data = self
                     .positions_file_slice
                     .read_bytes_slice(term_info.positions_range.clone())?;
@@ -261,9 +241,8 @@ impl InvertedIndexReader {
             }
         };
         Ok(SegmentPostings::from_block_postings(
-            block_segment_postings,
+            block_postings,
             position_reader,
-            position_within_block,
         ))
     }
 
@@ -289,7 +268,7 @@ impl InvertedIndexReader {
         option: IndexRecordOption,
     ) -> io::Result<Option<SegmentPostings>> {
         self.get_term_info(term)?
-            .map(move |term_info| self.read_postings_from_terminfo(&term_info, option, 0u32))
+            .map(move |term_info| self.read_postings_from_terminfo(&term_info, option))
             .transpose()
     }
 

src/indexer/delete_queue.rs

@@ -4,19 +4,20 @@ use std::sync::{Arc, RwLock, Weak};
 use super::operation::DeleteOperation;
 use crate::Opstamp;
 
-// The DeleteQueue is similar in conceptually to a multiple
+/// The DeleteQueue is similar in conceptually to a multiple
-// consumer single producer broadcast channel.
+/// consumer single producer broadcast channel.
-//
+///
-// All consumer will receive all messages.
+/// All consumer will receive all messages.
-//
+///
-// Consumer of the delete queue are holding a `DeleteCursor`,
+/// Consumer of the delete queue are holding a `DeleteCursor`,
-// which points to a specific place of the `DeleteQueue`.
+/// which points to a specific place of the `DeleteQueue`.
-//
+///
-// New consumer can be created in two ways
+/// New consumer can be created in two ways
-// - calling `delete_queue.cursor()` returns a cursor, that will include all future delete operation
+/// - calling `delete_queue.cursor()` returns a cursor, that will include all future delete
-//   (and some or none of the past operations... The client is in charge of checking the opstamps.).
+///   operation (and some or none of the past operations... The client is in charge of checking the
-// - cloning an existing cursor returns a new cursor, that is at the exact same position, and can
+///   opstamps.).
-//   now advance independently from the original cursor.
+/// - cloning an existing cursor returns a new cursor, that is at the exact same position, and can
+///   now advance independently from the original cursor.
 #[derive(Default)]
 struct InnerDeleteQueue {
     writer: Vec<DeleteOperation>,
@@ -249,12 +250,7 @@ mod tests {
 
     struct DummyWeight;
     impl Weight for DummyWeight {
-        fn scorer(
+        fn scorer(&self, _reader: &SegmentReader, _boost: Score) -> crate::Result<Box<dyn Scorer>> {
-            &self,
-            _reader: &SegmentReader,
-            _boost: Score,
-            _seek_doc: DocId,
-        ) -> crate::Result<Box<dyn Scorer>> {
             Err(crate::TantivyError::InternalError("dummy impl".to_owned()))
         }
 

src/indexer/merger.rs

@@ -367,11 +367,8 @@ impl IndexMerger {
             for (segment_ord, term_info) in merged_terms.current_segment_ords_and_term_infos() {
                 let segment_reader = &self.readers[segment_ord];
                 let inverted_index: &InvertedIndexReader = &field_readers[segment_ord];
-                let segment_postings = inverted_index.read_postings_from_terminfo(
+                let segment_postings = inverted_index
-                    &term_info,
+                    .read_postings_from_terminfo(&term_info, segment_postings_option)?;
-                    segment_postings_option,
-                    0u32,
-                )?;
                 let alive_bitset_opt = segment_reader.alive_bitset();
                 let doc_freq = if let Some(alive_bitset) = alive_bitset_opt {
                     segment_postings.doc_freq_given_deletes(alive_bitset)

src/indexer/mod.rs

@@ -4,6 +4,7 @@
 //! `IndexWriter` is the main entry point for that, which created from
 //! [`Index::writer`](crate::Index::writer).
 
+/// Delete queue implementation for broadcasting delete operations to consumers.
 pub(crate) mod delete_queue;
 pub(crate) mod path_to_unordered_id;
 

src/indexer/segment_writer.rs

@@ -421,10 +421,9 @@ fn remap_and_write(
 #[cfg(test)]
 mod tests {
     use std::collections::BTreeMap;
-    use std::path::{Path, PathBuf};
+    use std::path::Path;
 
     use columnar::ColumnType;
-    use tempfile::TempDir;
 
     use crate::collector::{Count, TopDocs};
     use crate::directory::RamDirectory;
@@ -1067,10 +1066,7 @@ mod tests {
         let mut schema_builder = Schema::builder();
         schema_builder.add_text_field("title", text_options);
         let schema = schema_builder.build();
-        let tempdir = TempDir::new().unwrap();
+        let index = Index::create_in_ram(schema);
-        let tempdir_path = PathBuf::from(tempdir.path());
-        Index::create_in_dir(&tempdir_path, schema).unwrap();
-        let index = Index::open_in_dir(tempdir_path).unwrap();
         let schema = index.schema();
         let mut index_writer = index.writer(50_000_000).unwrap();
         let title = schema.get_field("title").unwrap();

src/lib.rs

@@ -17,6 +17,7 @@
 //!
 //! ```rust
 //! # use std::path::Path;
+//! # use std::fs;
 //! # use tempfile::TempDir;
 //! # use tantivy::collector::TopDocs;
 //! # use tantivy::query::QueryParser;
@@ -27,8 +28,11 @@
 //! #     // Let's create a temporary directory for the
 //! #     // sake of this example
 //! #     if let Ok(dir) = TempDir::new() {
-//! #         run_example(dir.path()).unwrap();
+//! #         let index_path = dir.path().join("index");
-//! #         dir.close().unwrap();
+//! #         // In case the directory already exists, we remove it
+//! #         let _ = fs::remove_dir_all(&index_path);
+//! #         fs::create_dir_all(&index_path).unwrap();
+//! #         run_example(&index_path).unwrap();
 //! #     }
 //! # }
 //! #
@@ -203,6 +207,7 @@ mod docset;
 mod reader;
 
 #[cfg(test)]
+#[cfg(feature = "mmap")]
 mod compat_tests;
 
 pub use self::reader::{IndexReader, IndexReaderBuilder, ReloadPolicy, Warmer};
@@ -1170,12 +1175,11 @@ pub mod tests {
 
     #[test]
     fn test_validate_checksum() -> crate::Result<()> {
-        let index_path = tempfile::tempdir().expect("dir");
         let mut builder = Schema::builder();
         let body = builder.add_text_field("body", TEXT | STORED);
         let schema = builder.build();
-        let index = Index::create_in_dir(&index_path, schema)?;
+        let index = Index::create_in_ram(schema);
-        let mut writer: IndexWriter = index.writer(50_000_000)?;
+        let mut writer: IndexWriter = index.writer_for_tests()?;
         writer.set_merge_policy(Box::new(NoMergePolicy));
         for _ in 0..5000 {
             writer.add_document(doc!(body => "foo"))?;

src/postings/block_segment_postings.rs

@@ -99,8 +99,7 @@ impl BlockSegmentPostings {
         data: FileSlice,
         mut record_option: IndexRecordOption,
         requested_option: IndexRecordOption,
-        seek_doc: DocId,
+    ) -> io::Result<BlockSegmentPostings> {
-    ) -> io::Result<(BlockSegmentPostings, usize)> {
         let bytes = data.read_bytes()?;
         let (skip_data_opt, postings_data) = split_into_skips_and_postings(doc_freq, bytes)?;
         let skip_reader = match skip_data_opt {
@@ -126,7 +125,7 @@ impl BlockSegmentPostings {
             (_, _) => FreqReadingOption::ReadFreq,
         };
 
-        let mut block_segment_postings: BlockSegmentPostings = BlockSegmentPostings {
+        let mut block_segment_postings = BlockSegmentPostings {
             doc_decoder: BlockDecoder::with_val(TERMINATED),
             block_loaded: false,
             freq_decoder: BlockDecoder::with_val(1),
@@ -136,13 +135,8 @@ impl BlockSegmentPostings {
             data: postings_data,
             skip_reader,
         };
-        let inner_pos = if seek_doc == 0 {
+        block_segment_postings.load_block();
-            block_segment_postings.load_block();
+        Ok(block_segment_postings)
-            0
-        } else {
-            block_segment_postings.seek(seek_doc)
-        };
-        Ok((block_segment_postings, inner_pos))
     }
 
     /// Returns the block_max_score for the current block.
@@ -264,9 +258,7 @@ impl BlockSegmentPostings {
         self.doc_decoder.output_len
     }
 
-    /// Position on a block that may contains `target_doc`, and returns the
+    /// Position on a block that may contains `target_doc`.
-    /// position of the first document greater than or equal to `target_doc`
-    /// within that block.
     ///
     /// If all docs are smaller than target, the block loaded may be empty,
     /// or be the last an incomplete VInt block.
@@ -461,7 +453,7 @@ mod tests {
         doc_ids.push(130);
         {
             let block_segments = build_block_postings(&doc_ids)?;
-            let mut docset = SegmentPostings::from_block_postings(block_segments, None, 0);
+            let mut docset = SegmentPostings::from_block_postings(block_segments, None);
             assert_eq!(docset.seek(128), 129);
             assert_eq!(docset.doc(), 129);
             assert_eq!(docset.advance(), 130);
@@ -469,8 +461,8 @@ mod tests {
             assert_eq!(docset.advance(), TERMINATED);
         }
         {
-            let block_segments = build_block_postings(&doc_ids)?;
+            let block_segments = build_block_postings(&doc_ids).unwrap();
-            let mut docset = SegmentPostings::from_block_postings(block_segments, None, 0);
+            let mut docset = SegmentPostings::from_block_postings(block_segments, None);
             assert_eq!(docset.seek(129), 129);
             assert_eq!(docset.doc(), 129);
             assert_eq!(docset.advance(), 130);
@@ -479,7 +471,7 @@ mod tests {
         }
         {
             let block_segments = build_block_postings(&doc_ids)?;
-            let mut docset = SegmentPostings::from_block_postings(block_segments, None, 0);
+            let mut docset = SegmentPostings::from_block_postings(block_segments, None);
             assert_eq!(docset.doc(), 0);
             assert_eq!(docset.seek(131), TERMINATED);
             assert_eq!(docset.doc(), TERMINATED);

src/postings/mod.rs

@@ -527,6 +527,7 @@ pub(crate) mod tests {
     }
 
     impl<TScorer: Scorer> Scorer for UnoptimizedDocSet<TScorer> {
+        #[inline]
         fn score(&mut self) -> Score {
             self.0.score()
         }

src/postings/segment_postings.rs

@@ -79,15 +79,14 @@ impl SegmentPostings {
                 .close_term(docs.len() as u32)
                 .expect("In memory Serialization should never fail.");
         }
-        let (block_segment_postings, position_within_block) = BlockSegmentPostings::open(
+        let block_segment_postings = BlockSegmentPostings::open(
             docs.len() as u32,
             FileSlice::from(buffer),
             IndexRecordOption::Basic,
             IndexRecordOption::Basic,
-            0u32,
         )
         .unwrap();
-        SegmentPostings::from_block_postings(block_segment_postings, None, position_within_block)
+        SegmentPostings::from_block_postings(block_segment_postings, None)
     }
 
     /// Helper functions to create `SegmentPostings` for tests.
@@ -128,29 +127,28 @@ impl SegmentPostings {
         postings_serializer
             .close_term(doc_and_tfs.len() as u32)
             .unwrap();
-        let (block_segment_postings, position_within_block) = BlockSegmentPostings::open(
+        let block_segment_postings = BlockSegmentPostings::open(
             doc_and_tfs.len() as u32,
             FileSlice::from(buffer),
             IndexRecordOption::WithFreqs,
             IndexRecordOption::WithFreqs,
-            0u32,
         )
         .unwrap();
-        SegmentPostings::from_block_postings(block_segment_postings, None, position_within_block)
+        SegmentPostings::from_block_postings(block_segment_postings, None)
     }
 
-    /// Creates a Segment Postings from a
+    /// Reads a Segment postings from an &[u8]
-    /// - `BlockSegmentPostings`,
+    ///
-    /// - a position reader
+    /// * `len` - number of document in the posting lists.
-    /// - a target document to seek to
+    /// * `data` - data array. The complete data is not necessarily used.
+    /// * `freq_handler` - the freq handler is in charge of decoding frequencies and/or positions
     pub(crate) fn from_block_postings(
         segment_block_postings: BlockSegmentPostings,
         position_reader: Option<PositionReader>,
-        position_within_block: usize,
     ) -> SegmentPostings {
         SegmentPostings {
             block_cursor: segment_block_postings,
-            cur: position_within_block,
+            cur: 0, // cursor within the block
             position_reader,
         }
     }

src/postings/skip.rs

@@ -6,17 +6,21 @@ use crate::{DocId, Score, TERMINATED};
 
 // doc num bits uses the following encoding:
 // given 0b a b cdefgh
-//         |1|2|   3  |
+//         |1|2|3|  4  |
 // - 1: unused
 // - 2: is delta-1 encoded. 0 if not, 1, if yes
-// - 3: a 6 bit number in 0..=32, the actual bitwidth
+// - 3: unused
+// - 4: a 5 bit number in 0..32, the actual bitwidth. Bitpacking could in theory say this is 32
+//   (requiring a 6th bit), but the biggest doc_id we can want to encode is TERMINATED-1, which can
+//   be represented on 31b without delta encoding.
 fn encode_bitwidth(bitwidth: u8, delta_1: bool) -> u8 {
+    assert!(bitwidth < 32);
     bitwidth | ((delta_1 as u8) << 6)
 }
 
 fn decode_bitwidth(raw_bitwidth: u8) -> (u8, bool) {
     let delta_1 = ((raw_bitwidth >> 6) & 1) != 0;
-    let bitwidth = raw_bitwidth & 0x3f;
+    let bitwidth = raw_bitwidth & 0x1f;
     (bitwidth, delta_1)
 }
 
@@ -430,7 +434,7 @@ mod tests {
 
     #[test]
     fn test_encode_decode_bitwidth() {
-        for bitwidth in 0..=32 {
+        for bitwidth in 0..32 {
             for delta_1 in [false, true] {
                 assert_eq!(
                     (bitwidth, delta_1),

src/query/all_query.rs

@@ -21,12 +21,7 @@ impl Query for AllQuery {
 pub struct AllWeight;
 
 impl Weight for AllWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        _seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         let all_scorer = AllScorer::new(reader.max_doc());
         if boost != 1.0 {
             Ok(Box::new(BoostScorer::new(all_scorer, boost)))
@@ -110,6 +105,7 @@ impl DocSet for AllScorer {
 }
 
 impl Scorer for AllScorer {
+    #[inline]
     fn score(&mut self) -> Score {
         1.0
     }
@@ -145,7 +141,7 @@ mod tests {
         let weight = AllQuery.weight(EnableScoring::disabled_from_schema(&index.schema()))?;
         {
             let reader = searcher.segment_reader(0);
-            let mut scorer = weight.scorer(reader, 1.0, 0)?;
+            let mut scorer = weight.scorer(reader, 1.0)?;
             assert_eq!(scorer.doc(), 0u32);
             assert_eq!(scorer.advance(), 1u32);
             assert_eq!(scorer.doc(), 1u32);
@@ -153,7 +149,7 @@ mod tests {
         }
         {
             let reader = searcher.segment_reader(1);
-            let mut scorer = weight.scorer(reader, 1.0, 0)?;
+            let mut scorer = weight.scorer(reader, 1.0)?;
             assert_eq!(scorer.doc(), 0u32);
             assert_eq!(scorer.advance(), TERMINATED);
         }
@@ -168,12 +164,12 @@ mod tests {
         let weight = AllQuery.weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
         let reader = searcher.segment_reader(0);
         {
-            let mut scorer = weight.scorer(reader, 2.0, 0)?;
+            let mut scorer = weight.scorer(reader, 2.0)?;
             assert_eq!(scorer.doc(), 0u32);
             assert_eq!(scorer.score(), 2.0);
         }
         {
-            let mut scorer = weight.scorer(reader, 1.5, 0)?;
+            let mut scorer = weight.scorer(reader, 1.5)?;
             assert_eq!(scorer.doc(), 0u32);
             assert_eq!(scorer.score(), 1.5);
         }

src/query/automaton_weight.rs

@@ -84,12 +84,7 @@ where
     A: Automaton + Send + Sync + 'static,
     A::State: Clone,
 {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         let max_doc = reader.max_doc();
         let mut doc_bitset = BitSet::with_max_value(max_doc);
         let inverted_index = reader.inverted_index(self.field)?;
@@ -97,12 +92,8 @@ where
         let mut term_stream = self.automaton_stream(term_dict)?;
         while term_stream.advance() {
             let term_info = term_stream.value();
-            let (mut block_segment_postings, _) = inverted_index
+            let mut block_segment_postings = inverted_index
-                .read_block_postings_from_terminfo_with_seek(
+                .read_block_postings_from_terminfo(term_info, IndexRecordOption::Basic)?;
-                    term_info,
-                    IndexRecordOption::Basic,
-                    seek_doc,
-                )?;
             loop {
                 let docs = block_segment_postings.docs();
                 if docs.is_empty() {
@@ -120,7 +111,7 @@ where
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         if scorer.seek(doc) == doc {
             Ok(Explanation::new("AutomatonScorer", 1.0))
         } else {
@@ -195,7 +186,7 @@ mod tests {
         let automaton_weight = AutomatonWeight::new(field, PrefixedByA);
         let reader = index.reader()?;
         let searcher = reader.searcher();
-        let mut scorer = automaton_weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+        let mut scorer = automaton_weight.scorer(searcher.segment_reader(0u32), 1.0)?;
         assert_eq!(scorer.doc(), 0u32);
         assert_eq!(scorer.score(), 1.0);
         assert_eq!(scorer.advance(), 2u32);
@@ -212,7 +203,7 @@ mod tests {
         let automaton_weight = AutomatonWeight::new(field, PrefixedByA);
         let reader = index.reader()?;
         let searcher = reader.searcher();
-        let mut scorer = automaton_weight.scorer(searcher.segment_reader(0u32), 1.32, 0)?;
+        let mut scorer = automaton_weight.scorer(searcher.segment_reader(0u32), 1.32)?;
         assert_eq!(scorer.doc(), 0u32);
         assert_eq!(scorer.score(), 1.32);
         Ok(())

src/query/boolean_query/boolean_weight.rs

@@ -12,7 +12,7 @@ use crate::query::{
     intersect_scorers, AllScorer, BufferedUnionScorer, EmptyScorer, Exclude, Explanation, Occur,
     RequiredOptionalScorer, Scorer, Weight,
 };
-use crate::{DocId, Score, TERMINATED};
+use crate::{DocId, Score};
 
 enum SpecializedScorer {
     TermUnion(Vec<TermScorer>),
@@ -156,19 +156,6 @@ fn effective_should_scorer_for_union<TScoreCombiner: ScoreCombiner>(
     }
 }
 
-fn create_scorer(
-    weight: &dyn Weight,
-    reader: &SegmentReader,
-    boost: Score,
-    target_doc: DocId,
-) -> crate::Result<Box<dyn Scorer>> {
-    if target_doc >= reader.max_doc() {
-        Ok(Box::new(EmptyScorer))
-    } else {
-        weight.scorer(reader, boost, target_doc)
-    }
-}
-
 enum ShouldScorersCombinationMethod {
     // Should scorers are irrelevant.
     Ignored,
@@ -220,29 +207,10 @@ impl<TScoreCombiner: ScoreCombiner> BooleanWeight<TScoreCombiner> {
         &self,
         reader: &SegmentReader,
         boost: Score,
-        mut seek_first_doc: DocId,
     ) -> crate::Result<HashMap<Occur, Vec<Box<dyn Scorer>>>> {
         let mut per_occur_scorers: HashMap<Occur, Vec<Box<dyn Scorer>>> = HashMap::new();
-        let (mut must_weights, other_weights): (Vec<(Occur, _)>, Vec<(Occur, _)>) = self
+        for (occur, subweight) in &self.weights {
-            .weights
+            let sub_scorer: Box<dyn Scorer> = subweight.scorer(reader, boost)?;
-            .iter()
-            .map(|(occur, weight)| (*occur, weight))
-            .partition(|(occur, _weight)| *occur == Occur::Must);
-        // We start by must weights in order to get the best "seek_first_doc" so that we
-        // can skip the first few documents of the other scorers.
-        must_weights.sort_by_key(|weight| weight.1.intersection_priority());
-        for (_, must_sub_weight) in must_weights {
-            let sub_scorer: Box<dyn Scorer> =
-                create_scorer(must_sub_weight.as_ref(), reader, boost, seek_first_doc)?;
-            seek_first_doc = seek_first_doc.max(sub_scorer.doc());
-            per_occur_scorers
-                .entry(Occur::Must)
-                .or_default()
-                .push(sub_scorer);
-        }
-        for (occur, sub_weight) in &other_weights {
-            let sub_scorer: Box<dyn Scorer> =
-                create_scorer(sub_weight.as_ref(), reader, boost, seek_first_doc)?;
             per_occur_scorers
                 .entry(*occur)
                 .or_default()
@@ -256,10 +224,9 @@ impl<TScoreCombiner: ScoreCombiner> BooleanWeight<TScoreCombiner> {
         reader: &SegmentReader,
         boost: Score,
         score_combiner_fn: impl Fn() -> TComplexScoreCombiner,
-        seek_doc: u32,
     ) -> crate::Result<SpecializedScorer> {
         let num_docs = reader.num_docs();
-        let mut per_occur_scorers = self.per_occur_scorers(reader, boost, seek_doc)?;
+        let mut per_occur_scorers = self.per_occur_scorers(reader, boost)?;
 
         // Indicate how should clauses are combined with must clauses.
         let mut must_scorers: Vec<Box<dyn Scorer>> =
@@ -440,7 +407,7 @@ fn remove_and_count_all_and_empty_scorers(
         if scorer.is::<AllScorer>() {
             counts.num_all_scorers += 1;
             false
-        } else if scorer.doc() == TERMINATED {
+        } else if scorer.is::<EmptyScorer>() {
             counts.num_empty_scorers += 1;
             false
         } else {
@@ -451,12 +418,7 @@ fn remove_and_count_all_and_empty_scorers(
 }
 
 impl<TScoreCombiner: ScoreCombiner + Sync> Weight for BooleanWeight<TScoreCombiner> {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         let num_docs = reader.num_docs();
         if self.weights.is_empty() {
             Ok(Box::new(EmptyScorer))
@@ -465,15 +427,15 @@ impl<TScoreCombiner: ScoreCombiner + Sync> Weight for BooleanWeight<TScoreCombin
             if occur == Occur::MustNot {
                 Ok(Box::new(EmptyScorer))
             } else {
-                weight.scorer(reader, boost, seek_doc)
+                weight.scorer(reader, boost)
             }
         } else if self.scoring_enabled {
-            self.complex_scorer(reader, boost, &self.score_combiner_fn, seek_doc)
+            self.complex_scorer(reader, boost, &self.score_combiner_fn)
                 .map(|specialized_scorer| {
                     into_box_scorer(specialized_scorer, &self.score_combiner_fn, num_docs)
                 })
         } else {
-            self.complex_scorer(reader, boost, DoNothingCombiner::default, seek_doc)
+            self.complex_scorer(reader, boost, DoNothingCombiner::default)
                 .map(|specialized_scorer| {
                     into_box_scorer(specialized_scorer, DoNothingCombiner::default, num_docs)
                 })
@@ -481,7 +443,7 @@ impl<TScoreCombiner: ScoreCombiner + Sync> Weight for BooleanWeight<TScoreCombin
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         if scorer.seek(doc) != doc {
             return Err(does_not_match(doc));
         }
@@ -505,7 +467,7 @@ impl<TScoreCombiner: ScoreCombiner + Sync> Weight for BooleanWeight<TScoreCombin
         reader: &SegmentReader,
         callback: &mut dyn FnMut(DocId, Score),
     ) -> crate::Result<()> {
-        let scorer = self.complex_scorer(reader, 1.0, &self.score_combiner_fn, 0)?;
+        let scorer = self.complex_scorer(reader, 1.0, &self.score_combiner_fn)?;
         match scorer {
             SpecializedScorer::TermUnion(term_scorers) => {
                 let mut union_scorer = BufferedUnionScorer::build(
@@ -527,7 +489,7 @@ impl<TScoreCombiner: ScoreCombiner + Sync> Weight for BooleanWeight<TScoreCombin
         reader: &SegmentReader,
         callback: &mut dyn FnMut(&[DocId]),
     ) -> crate::Result<()> {
-        let scorer = self.complex_scorer(reader, 1.0, || DoNothingCombiner, 0u32)?;
+        let scorer = self.complex_scorer(reader, 1.0, || DoNothingCombiner)?;
         let mut buffer = [0u32; COLLECT_BLOCK_BUFFER_LEN];
 
         match scorer {
@@ -562,7 +524,7 @@ impl<TScoreCombiner: ScoreCombiner + Sync> Weight for BooleanWeight<TScoreCombin
         reader: &SegmentReader,
         callback: &mut dyn FnMut(DocId, Score) -> Score,
     ) -> crate::Result<()> {
-        let scorer = self.complex_scorer(reader, 1.0, &self.score_combiner_fn, 0u32)?;
+        let scorer = self.complex_scorer(reader, 1.0, &self.score_combiner_fn)?;
         match scorer {
             SpecializedScorer::TermUnion(term_scorers) => {
                 super::block_wand(term_scorers, threshold, callback);

src/query/boolean_query/mod.rs

@@ -57,7 +57,7 @@ mod tests {
         let query = query_parser.parse_query("+a")?;
         let searcher = index.reader()?.searcher();
         let weight = query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
-        let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+        let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0)?;
         assert!(scorer.is::<TermScorer>());
         Ok(())
     }
@@ -70,13 +70,13 @@ mod tests {
         {
             let query = query_parser.parse_query("+a +b +c")?;
             let weight = query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0)?;
             assert!(scorer.is::<Intersection<TermScorer>>());
         }
         {
             let query = query_parser.parse_query("+a +(b c)")?;
             let weight = query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0)?;
             assert!(scorer.is::<Intersection<Box<dyn Scorer>>>());
         }
         Ok(())
@@ -90,14 +90,14 @@ mod tests {
         {
             let query = query_parser.parse_query("+a b")?;
             let weight = query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0)?;
             assert!(scorer
                 .is::<RequiredOptionalScorer<Box<dyn Scorer>, Box<dyn Scorer>, SumCombiner>>());
         }
         {
             let query = query_parser.parse_query("+a b")?;
             let weight = query.weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0)?;
             assert!(scorer.is::<TermScorer>());
         }
         Ok(())
@@ -244,14 +244,12 @@ mod tests {
             .weight(EnableScoring::enabled_from_searcher(&searcher))
             .unwrap();
         {
-            let mut boolean_scorer =
+            let mut boolean_scorer = boolean_weight.scorer(searcher.segment_reader(0u32), 1.0)?;
-                boolean_weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
             assert_eq!(boolean_scorer.doc(), 0u32);
             assert_nearly_equals!(boolean_scorer.score(), 0.84163445);
         }
         {
-            let mut boolean_scorer =
+            let mut boolean_scorer = boolean_weight.scorer(searcher.segment_reader(0u32), 2.0)?;
-                boolean_weight.scorer(searcher.segment_reader(0u32), 2.0, 0)?;
             assert_eq!(boolean_scorer.doc(), 0u32);
             assert_nearly_equals!(boolean_scorer.score(), 1.6832689);
         }
@@ -345,7 +343,7 @@ mod tests {
                 (Occur::Must, term_match_some.box_clone()),
             ]);
             let weight = query.weight(EnableScoring::disabled_from_searcher(&searcher))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32)?;
             assert!(scorer.is::<TermScorer>());
         }
         {
@@ -355,7 +353,7 @@ mod tests {
                 (Occur::Must, term_match_none.box_clone()),
             ]);
             let weight = query.weight(EnableScoring::disabled_from_searcher(&searcher))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32)?;
             assert!(scorer.is::<EmptyScorer>());
         }
         {
@@ -364,7 +362,7 @@ mod tests {
                 (Occur::Should, term_match_none.box_clone()),
             ]);
             let weight = query.weight(EnableScoring::disabled_from_searcher(&searcher))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32)?;
             assert!(scorer.is::<AllScorer>());
         }
         {
@@ -373,7 +371,7 @@ mod tests {
                 (Occur::Should, term_match_none.box_clone()),
             ]);
             let weight = query.weight(EnableScoring::disabled_from_searcher(&searcher))?;
-            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32, 0)?;
+            let scorer = weight.scorer(searcher.segment_reader(0u32), 1.0f32)?;
             assert!(scorer.is::<TermScorer>());
         }
         Ok(())
@@ -613,134 +611,6 @@ mod tests {
         Ok(())
     }
 
-    /// Test that the seek_doc parameter correctly skips documents in BooleanWeight::scorer.
-    ///
-    /// When seek_doc is provided, the scorer should start from that document (or the first
-    /// matching document >= seek_doc), skipping earlier documents.
-    #[test]
-    pub fn test_boolean_weight_seek_doc() -> crate::Result<()> {
-        let mut schema_builder = Schema::builder();
-        let text_field = schema_builder.add_text_field("text", TEXT);
-        let value_field = schema_builder.add_u64_field("value", FAST);
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer: IndexWriter = index.writer_for_tests()?;
-
-        // Create 11 documents:
-        // doc 0: value=0
-        // doc 1: value=10
-        // doc 2: value=20
-        // ...
-        // doc 9: value=90
-        // doc 10: value=50 (matches range 30-70)
-        for i in 0..10 {
-            index_writer.add_document(doc!(
-                text_field => "hello",
-                value_field => (i * 10) as u64
-            ))?;
-        }
-        index_writer.add_document(doc!(
-            text_field => "hello",
-            value_field => 50u64
-        ))?;
-        index_writer.commit()?;
-
-        let searcher = index.reader()?.searcher();
-        let segment_reader = searcher.segment_reader(0);
-
-        // Create a Boolean query: MUST(term "hello") AND MUST(range 30..=70)
-        // This should match docs with value in [30, 70]: docs 3, 4, 5, 6, 7, 10
-        let term_query: Box<dyn Query> = Box::new(TermQuery::new(
-            Term::from_field_text(text_field, "hello"),
-            IndexRecordOption::Basic,
-        ));
-        let range_query: Box<dyn Query> = Box::new(RangeQuery::new(
-            Bound::Included(Term::from_field_u64(value_field, 30)),
-            Bound::Included(Term::from_field_u64(value_field, 70)),
-        ));
-
-        let boolean_query =
-            BooleanQuery::new(vec![(Occur::Must, term_query), (Occur::Must, range_query)]);
-
-        let weight =
-            boolean_query.weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
-
-        let doc_when_seeking_from = |seek_from: DocId| {
-            let scorer = weight.scorer(segment_reader, 1.0f32, seek_from).unwrap();
-            crate::docset::docset_to_doc_vec(scorer)
-        };
-
-        // Expected matching docs: 3, 4, 5, 6, 7, 10 (values 30, 40, 50, 60, 70, 50)
-        assert_eq!(doc_when_seeking_from(0), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(1), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(3), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(4), vec![4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(7), vec![7, 10]);
-        assert_eq!(doc_when_seeking_from(8), vec![10]);
-        assert_eq!(doc_when_seeking_from(10), vec![10]);
-        assert_eq!(doc_when_seeking_from(11), Vec::<DocId>::new());
-
-        Ok(())
-    }
-
-    /// Test that the seek_doc parameter works correctly with SHOULD clauses.
-    #[test]
-    pub fn test_boolean_weight_seek_doc_with_should() -> crate::Result<()> {
-        let mut schema_builder = Schema::builder();
-        let text_field = schema_builder.add_text_field("text", TEXT);
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer: IndexWriter = index.writer_for_tests()?;
-
-        // Create documents:
-        // doc 0: "a b"
-        // doc 1: "a"
-        // doc 2: "b"
-        // doc 3: "c"
-        // doc 4: "a b c"
-        index_writer.add_document(doc!(text_field => "a b"))?;
-        index_writer.add_document(doc!(text_field => "a"))?;
-        index_writer.add_document(doc!(text_field => "b"))?;
-        index_writer.add_document(doc!(text_field => "c"))?;
-        index_writer.add_document(doc!(text_field => "a b c"))?;
-        index_writer.commit()?;
-
-        let searcher = index.reader()?.searcher();
-        let segment_reader = searcher.segment_reader(0);
-
-        // Create a Boolean query: SHOULD(term "a") OR SHOULD(term "b")
-        // This should match docs 0, 1, 2, 4
-        let term_a: Box<dyn Query> = Box::new(TermQuery::new(
-            Term::from_field_text(text_field, "a"),
-            IndexRecordOption::Basic,
-        ));
-        let term_b: Box<dyn Query> = Box::new(TermQuery::new(
-            Term::from_field_text(text_field, "b"),
-            IndexRecordOption::Basic,
-        ));
-
-        let boolean_query =
-            BooleanQuery::new(vec![(Occur::Should, term_a), (Occur::Should, term_b)]);
-
-        let weight =
-            boolean_query.weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
-
-        let doc_when_seeking_from = |seek_from: DocId| {
-            let scorer = weight.scorer(segment_reader, 1.0f32, seek_from).unwrap();
-            crate::docset::docset_to_doc_vec(scorer)
-        };
-
-        // Expected matching docs: 0, 1, 2, 4
-        assert_eq!(doc_when_seeking_from(0), vec![0, 1, 2, 4]);
-        assert_eq!(doc_when_seeking_from(1), vec![1, 2, 4]);
-        assert_eq!(doc_when_seeking_from(2), vec![2, 4]);
-        assert_eq!(doc_when_seeking_from(3), vec![4]);
-        assert_eq!(doc_when_seeking_from(4), vec![4]);
-        assert_eq!(doc_when_seeking_from(5), Vec::<DocId>::new());
-
-        Ok(())
-    }
-
     /// Test multiple AllScorer instances in different clause types.
     ///
     /// Verifies correct behavior when AllScorers appear in multiple positions.

src/query/boost_query.rs

@@ -67,13 +67,8 @@ impl BoostWeight {
 }
 
 impl Weight for BoostWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
+        self.weight.scorer(reader, boost * self.boost)
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
-        self.weight.scorer(reader, boost * self.boost, seek_doc)
     }
 
     fn explain(&self, reader: &SegmentReader, doc: u32) -> crate::Result<Explanation> {
@@ -88,10 +83,6 @@ impl Weight for BoostWeight {
     fn count(&self, reader: &SegmentReader) -> crate::Result<u32> {
         self.weight.count(reader)
     }
-
-    fn intersection_priority(&self) -> u32 {
-        self.weight.intersection_priority()
-    }
 }
 
 pub(crate) struct BoostScorer<S: Scorer> {
@@ -143,6 +134,7 @@ impl<S: Scorer> DocSet for BoostScorer<S> {
 }
 
 impl<S: Scorer> Scorer for BoostScorer<S> {
+    #[inline]
     fn score(&mut self) -> Score {
         self.underlying.score() * self.boost
     }

src/query/const_score_query.rs

@@ -63,18 +63,13 @@ impl ConstWeight {
 }
 
 impl Weight for ConstWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
+        let inner_scorer = self.weight.scorer(reader, boost)?;
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
-        let inner_scorer = self.weight.scorer(reader, boost, seek_doc)?;
         Ok(Box::new(ConstScorer::new(inner_scorer, boost * self.score)))
     }
 
     fn explain(&self, reader: &SegmentReader, doc: u32) -> crate::Result<Explanation> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         if scorer.seek(doc) != doc {
             return Err(TantivyError::InvalidArgument(format!(
                 "Document #({doc}) does not match"
@@ -89,10 +84,6 @@ impl Weight for ConstWeight {
     fn count(&self, reader: &SegmentReader) -> crate::Result<u32> {
         self.weight.count(reader)
     }
-
-    fn intersection_priority(&self) -> u32 {
-        self.weight.intersection_priority()
-    }
 }
 
 /// Wraps a `DocSet` and simply returns a constant `Scorer`.
@@ -146,6 +137,7 @@ impl<TDocSet: DocSet> DocSet for ConstScorer<TDocSet> {
 }
 
 impl<TDocSet: DocSet + 'static> Scorer for ConstScorer<TDocSet> {
+    #[inline]
     fn score(&mut self) -> Score {
         self.score
     }

src/query/disjunction.rs

@@ -173,6 +173,7 @@ impl<TScorer: Scorer, TScoreCombiner: ScoreCombiner> DocSet
 impl<TScorer: Scorer, TScoreCombiner: ScoreCombiner> Scorer
     for Disjunction<TScorer, TScoreCombiner>
 {
+    #[inline]
     fn score(&mut self) -> Score {
         self.current_score
     }
@@ -307,6 +308,7 @@ mod tests {
     }
 
     impl Scorer for DummyScorer {
+        #[inline]
         fn score(&mut self) -> Score {
             self.foo.get(self.cursor).map(|x| x.1).unwrap_or(0.0)
         }

src/query/empty_query.rs

@@ -26,24 +26,13 @@ impl Query for EmptyQuery {
 /// It is useful for tests and handling edge cases.
 pub struct EmptyWeight;
 impl Weight for EmptyWeight {
-    fn scorer(
+    fn scorer(&self, _reader: &SegmentReader, _boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        _reader: &SegmentReader,
-        _boost: Score,
-        _seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         Ok(Box::new(EmptyScorer))
     }
 
     fn explain(&self, _reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
         Err(does_not_match(doc))
     }
-
-    /// Returns a priority number used to sort weights when running an
-    /// intersection.
-    fn intersection_priority(&self) -> u32 {
-        0u32
-    }
 }
 
 /// `EmptyScorer` is a dummy `Scorer` in which no document matches.
@@ -66,6 +55,7 @@ impl DocSet for EmptyScorer {
 }
 
 impl Scorer for EmptyScorer {
+    #[inline]
     fn score(&mut self) -> Score {
         0.0
     }

src/query/exclude.rs

@@ -84,6 +84,7 @@ where
     TScorer: Scorer,
     TDocSetExclude: DocSet + 'static,
 {
+    #[inline]
     fn score(&mut self) -> Score {
         self.underlying_docset.score()
     }

src/query/exist_query.rs

@@ -98,12 +98,7 @@ pub struct ExistsWeight {
 }
 
 impl Weight for ExistsWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        _seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         let fast_field_reader = reader.fast_fields();
         let mut column_handles = fast_field_reader.dynamic_column_handles(&self.field_name)?;
         if self.field_type == Type::Json && self.json_subpaths {
@@ -171,7 +166,7 @@ impl Weight for ExistsWeight {
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         if scorer.seek(doc) != doc {
             return Err(does_not_match(doc));
         }

src/query/intersection.rs

@@ -105,6 +105,7 @@ impl<TDocSet: DocSet> Intersection<TDocSet, TDocSet> {
 }
 
 impl<TDocSet: DocSet, TOtherDocSet: DocSet> DocSet for Intersection<TDocSet, TOtherDocSet> {
+    #[inline]
     fn advance(&mut self) -> DocId {
         let (left, right) = (&mut self.left, &mut self.right);
         let mut candidate = left.advance();
@@ -174,6 +175,7 @@ impl<TDocSet: DocSet, TOtherDocSet: DocSet> DocSet for Intersection<TDocSet, TOt
                 .all(|docset| docset.seek_into_the_danger_zone(target))
     }
 
+    #[inline]
     fn doc(&self) -> DocId {
         self.left.doc()
     }
@@ -200,6 +202,7 @@ where
     TScorer: Scorer,
     TOtherScorer: Scorer,
 {
+    #[inline]
     fn score(&mut self) -> Score {
         self.left.score()
             + self.right.score()

src/query/phrase_prefix_query/phrase_prefix_scorer.rs

@@ -81,6 +81,7 @@ impl<TPostings: Postings> DocSet for PhraseKind<TPostings> {
 }
 
 impl<TPostings: Postings> Scorer for PhraseKind<TPostings> {
+    #[inline]
     fn score(&mut self) -> Score {
         match self {
             PhraseKind::SinglePrefix { positions, .. } => {
@@ -215,6 +216,7 @@ impl<TPostings: Postings> DocSet for PhrasePrefixScorer<TPostings> {
 }
 
 impl<TPostings: Postings> Scorer for PhrasePrefixScorer<TPostings> {
+    #[inline]
     fn score(&mut self) -> Score {
         // TODO modify score??
         self.phrase_scorer.score()

src/query/phrase_prefix_query/phrase_prefix_weight.rs

@@ -42,11 +42,10 @@ impl PhrasePrefixWeight {
         Ok(FieldNormReader::constant(reader.max_doc(), 1))
     }
 
-    pub(crate) fn prefix_phrase_scorer(
+    pub(crate) fn phrase_scorer(
         &self,
         reader: &SegmentReader,
         boost: Score,
-        seek_doc: DocId,
     ) -> crate::Result<Option<PhrasePrefixScorer<SegmentPostings>>> {
         let similarity_weight_opt = self
             .similarity_weight_opt
@@ -55,16 +54,14 @@ impl PhrasePrefixWeight {
         let fieldnorm_reader = self.fieldnorm_reader(reader)?;
         let mut term_postings_list = Vec::new();
         for &(offset, ref term) in &self.phrase_terms {
-            let inverted_index = reader.inverted_index(term.field())?;
+            if let Some(postings) = reader
-            let Some(term_info) = inverted_index.get_term_info(term)? else {
+                .inverted_index(term.field())?
+                .read_postings(term, IndexRecordOption::WithFreqsAndPositions)?
+            {
+                term_postings_list.push((offset, postings));
+            } else {
                 return Ok(None);
-            };
+            }
-            let postings = inverted_index.read_postings_from_terminfo(
-                &term_info,
-                IndexRecordOption::WithFreqsAndPositions,
-                seek_doc,
-            )?;
-            term_postings_list.push((offset, postings));
         }
 
         let inv_index = reader.inverted_index(self.prefix.1.field())?;
@@ -117,13 +114,8 @@ impl PhrasePrefixWeight {
 }
 
 impl Weight for PhrasePrefixWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
+        if let Some(scorer) = self.phrase_scorer(reader, boost)? {
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
-        if let Some(scorer) = self.prefix_phrase_scorer(reader, boost, seek_doc)? {
             Ok(Box::new(scorer))
         } else {
             Ok(Box::new(EmptyScorer))
@@ -131,7 +123,7 @@ impl Weight for PhrasePrefixWeight {
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        let scorer_opt = self.prefix_phrase_scorer(reader, 1.0, doc)?;
+        let scorer_opt = self.phrase_scorer(reader, 1.0)?;
         if scorer_opt.is_none() {
             return Err(does_not_match(doc));
         }
@@ -148,10 +140,6 @@ impl Weight for PhrasePrefixWeight {
         }
         Ok(explanation)
     }
-
-    fn intersection_priority(&self) -> u32 {
-        50u32
-    }
 }
 
 #[cfg(test)]
@@ -199,7 +187,7 @@ mod tests {
             .unwrap()
             .unwrap();
         let mut phrase_scorer = phrase_weight
-            .prefix_phrase_scorer(searcher.segment_reader(0u32), 1.0, 0u32)?
+            .phrase_scorer(searcher.segment_reader(0u32), 1.0)?
             .unwrap();
         assert_eq!(phrase_scorer.doc(), 1);
         assert_eq!(phrase_scorer.phrase_count(), 2);
@@ -226,7 +214,7 @@ mod tests {
             .unwrap()
             .unwrap();
         let mut phrase_scorer = phrase_weight
-            .prefix_phrase_scorer(searcher.segment_reader(0u32), 1.0, 0u32)?
+            .phrase_scorer(searcher.segment_reader(0u32), 1.0)?
             .unwrap();
         assert_eq!(phrase_scorer.doc(), 1);
         assert_eq!(phrase_scorer.phrase_count(), 2);
@@ -250,7 +238,7 @@ mod tests {
             .unwrap()
             .is_none());
         let weight = phrase_query.weight(enable_scoring).unwrap();
-        let mut phrase_scorer = weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+        let mut phrase_scorer = weight.scorer(searcher.segment_reader(0u32), 1.0)?;
         assert_eq!(phrase_scorer.doc(), 1);
         assert_eq!(phrase_scorer.advance(), 2);
         assert_eq!(phrase_scorer.doc(), 2);
@@ -271,7 +259,7 @@ mod tests {
         ]);
         let enable_scoring = EnableScoring::enabled_from_searcher(&searcher);
         let weight = phrase_query.weight(enable_scoring).unwrap();
-        let mut phrase_scorer = weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+        let mut phrase_scorer = weight.scorer(searcher.segment_reader(0u32), 1.0)?;
         assert_eq!(phrase_scorer.advance(), TERMINATED);
         Ok(())
     }

src/query/phrase_query/mod.rs

@@ -84,7 +84,7 @@ pub(crate) mod tests {
         let phrase_query = PhraseQuery::new(terms);
         let phrase_weight =
             phrase_query.phrase_weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
-        let mut phrase_scorer = phrase_weight.scorer(searcher.segment_reader(0), 1.0, 0)?;
+        let mut phrase_scorer = phrase_weight.scorer(searcher.segment_reader(0), 1.0)?;
         assert_eq!(phrase_scorer.doc(), 1);
         assert_eq!(phrase_scorer.advance(), TERMINATED);
         Ok(())
@@ -343,43 +343,6 @@ pub(crate) mod tests {
         Ok(())
     }
 
-    #[test]
-    pub fn test_phrase_weight_seek_doc() -> crate::Result<()> {
-        // Create an index with documents where the phrase "a b" appears in some of them.
-        // Documents: 0: "c d", 1: "a b", 2: "e f", 3: "a b c", 4: "g h", 5: "a b", 6: "i j"
-        let index = create_index(&["c d", "a b", "e f", "a b c", "g h", "a b", "i j"])?;
-        let text_field = index.schema().get_field("text").unwrap();
-        let searcher = index.reader()?.searcher();
-        let segment_reader = searcher.segment_reader(0);
-
-        let phrase_query = PhraseQuery::new(vec![
-            Term::from_field_text(text_field, "a"),
-            Term::from_field_text(text_field, "b"),
-        ]);
-        let phrase_weight =
-            phrase_query.phrase_weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
-
-        // Helper function to collect all docs from a scorer created with a given seek_doc
-        let docs_when_seeking_from = |seek_from: DocId| {
-            let scorer = phrase_weight
-                .scorer(segment_reader, 1.0f32, seek_from)
-                .unwrap();
-            crate::docset::docset_to_doc_vec(scorer)
-        };
-
-        // Documents with "a b": 1, 3, 5
-        assert_eq!(docs_when_seeking_from(0), vec![1, 3, 5]);
-        assert_eq!(docs_when_seeking_from(1), vec![1, 3, 5]);
-        assert_eq!(docs_when_seeking_from(2), vec![3, 5]);
-        assert_eq!(docs_when_seeking_from(3), vec![3, 5]);
-        assert_eq!(docs_when_seeking_from(4), vec![5]);
-        assert_eq!(docs_when_seeking_from(5), vec![5]);
-        assert_eq!(docs_when_seeking_from(6), Vec::<DocId>::new());
-        assert_eq!(docs_when_seeking_from(7), Vec::<DocId>::new());
-
-        Ok(())
-    }
-
     #[test]
     pub fn test_phrase_query_on_json() -> crate::Result<()> {
         let mut schema_builder = Schema::builder();
@@ -410,7 +373,7 @@ pub(crate) mod tests {
                 .weight(EnableScoring::disabled_from_schema(searcher.schema()))
                 .unwrap();
             let mut phrase_scorer = phrase_weight
-                .scorer(searcher.segment_reader(0), 1.0f32, 0)
+                .scorer(searcher.segment_reader(0), 1.0f32)
                 .unwrap();
             let mut docs = Vec::new();
             loop {

src/query/phrase_query/phrase_scorer.rs

@@ -563,6 +563,7 @@ impl<TPostings: Postings> DocSet for PhraseScorer<TPostings> {
 }
 
 impl<TPostings: Postings> Scorer for PhraseScorer<TPostings> {
+    #[inline]
     fn score(&mut self) -> Score {
         let doc = self.doc();
         let fieldnorm_id = self.fieldnorm_reader.fieldnorm_id(doc);

src/query/phrase_query/phrase_weight.rs

@@ -43,7 +43,6 @@ impl PhraseWeight {
         &self,
         reader: &SegmentReader,
         boost: Score,
-        seek_doc: DocId,
     ) -> crate::Result<Option<PhraseScorer<SegmentPostings>>> {
         let similarity_weight_opt = self
             .similarity_weight_opt
@@ -52,16 +51,14 @@ impl PhraseWeight {
         let fieldnorm_reader = self.fieldnorm_reader(reader)?;
         let mut term_postings_list = Vec::new();
         for &(offset, ref term) in &self.phrase_terms {
-            let inverted_index = reader.inverted_index(term.field())?;
+            if let Some(postings) = reader
-            let Some(term_info) = inverted_index.get_term_info(term)? else {
+                .inverted_index(term.field())?
+                .read_postings(term, IndexRecordOption::WithFreqsAndPositions)?
+            {
+                term_postings_list.push((offset, postings));
+            } else {
                 return Ok(None);
-            };
+            }
-            let postings = inverted_index.read_postings_from_terminfo(
-                &term_info,
-                IndexRecordOption::WithFreqsAndPositions,
-                seek_doc,
-            )?;
-            term_postings_list.push((offset, postings));
         }
         Ok(Some(PhraseScorer::new(
             term_postings_list,
@@ -77,13 +74,8 @@ impl PhraseWeight {
 }
 
 impl Weight for PhraseWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
+        if let Some(scorer) = self.phrase_scorer(reader, boost)? {
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
-        if let Some(scorer) = self.phrase_scorer(reader, boost, seek_doc)? {
             Ok(Box::new(scorer))
         } else {
             Ok(Box::new(EmptyScorer))
@@ -91,12 +83,12 @@ impl Weight for PhraseWeight {
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        let scorer_opt = self.phrase_scorer(reader, 1.0, doc)?;
+        let scorer_opt = self.phrase_scorer(reader, 1.0)?;
         if scorer_opt.is_none() {
             return Err(does_not_match(doc));
         }
         let mut scorer = scorer_opt.unwrap();
-        if scorer.doc() != doc {
+        if scorer.seek(doc) != doc {
             return Err(does_not_match(doc));
         }
         let fieldnorm_reader = self.fieldnorm_reader(reader)?;
@@ -108,10 +100,6 @@ impl Weight for PhraseWeight {
         }
         Ok(explanation)
     }
-
-    fn intersection_priority(&self) -> u32 {
-        40u32
-    }
 }
 
 #[cfg(test)]
@@ -134,7 +122,7 @@ mod tests {
         let enable_scoring = EnableScoring::enabled_from_searcher(&searcher);
         let phrase_weight = phrase_query.phrase_weight(enable_scoring).unwrap();
         let mut phrase_scorer = phrase_weight
-            .phrase_scorer(searcher.segment_reader(0u32), 1.0, 0)?
+            .phrase_scorer(searcher.segment_reader(0u32), 1.0)?
             .unwrap();
         assert_eq!(phrase_scorer.doc(), 1);
         assert_eq!(phrase_scorer.phrase_count(), 2);

src/query/phrase_query/regex_phrase_weight.rs

@@ -195,11 +195,8 @@ impl RegexPhraseWeight {
         const SPARSE_TERM_DOC_THRESHOLD: u32 = 100;
 
         for term_info in term_infos {
-            let mut term_posting = inverted_index.read_postings_from_terminfo(
+            let mut term_posting = inverted_index
-                term_info,
+                .read_postings_from_terminfo(term_info, IndexRecordOption::WithFreqsAndPositions)?;
-                IndexRecordOption::WithFreqsAndPositions,
-                0u32,
-            )?;
             let num_docs = term_posting.doc_freq();
 
             if num_docs < SPARSE_TERM_DOC_THRESHOLD {
@@ -272,12 +269,7 @@ impl RegexPhraseWeight {
 }
 
 impl Weight for RegexPhraseWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        _seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         if let Some(scorer) = self.phrase_scorer(reader, boost)? {
             Ok(Box::new(scorer))
         } else {

src/query/range_query/fast_field_range_doc_set.rs

@@ -61,11 +61,7 @@ pub(crate) struct RangeDocSet<T> {
 
 const DEFAULT_FETCH_HORIZON: u32 = 128;
 impl<T: Send + Sync + PartialOrd + Copy + Debug + 'static> RangeDocSet<T> {
-    pub(crate) fn new(
+    pub(crate) fn new(value_range: RangeInclusive<T>, column: Column<T>) -> Self {
-        value_range: RangeInclusive<T>,
-        column: Column<T>,
-        seek_first_doc: DocId,
-    ) -> Self {
         if *value_range.start() > column.max_value() || *value_range.end() < column.min_value() {
             return Self {
                 value_range,
@@ -81,7 +77,7 @@ impl<T: Send + Sync + PartialOrd + Copy + Debug + 'static> RangeDocSet<T> {
             value_range,
             column,
             loaded_docs: VecCursor::new(),
-            next_fetch_start: seek_first_doc,
+            next_fetch_start: 0,
             fetch_horizon: DEFAULT_FETCH_HORIZON,
             last_seek_pos_opt: None,
         };

src/query/range_query/range_query.rs

@@ -212,12 +212,7 @@ impl InvertedIndexRangeWeight {
 }
 
 impl Weight for InvertedIndexRangeWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         let max_doc = reader.max_doc();
         let mut doc_bitset = BitSet::with_max_value(max_doc);
 
@@ -234,12 +229,7 @@ impl Weight for InvertedIndexRangeWeight {
             processed_count += 1;
             let term_info = term_range.value();
             let mut block_segment_postings = inverted_index
-                .read_block_postings_from_terminfo_with_seek(
+                .read_block_postings_from_terminfo(term_info, IndexRecordOption::Basic)?;
-                    term_info,
-                    IndexRecordOption::Basic,
-                    seek_doc,
-                )?
-                .0;
             loop {
                 let docs = block_segment_postings.docs();
                 if docs.is_empty() {
@@ -256,7 +246,7 @@ impl Weight for InvertedIndexRangeWeight {
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         if scorer.seek(doc) != doc {
             return Err(does_not_match(doc));
         }
@@ -696,7 +686,7 @@ mod tests {
                 .weight(EnableScoring::disabled_from_schema(&schema))
                 .unwrap();
             let range_scorer = range_weight
-                .scorer(&searcher.segment_readers()[0], 1.0f32, 0)
+                .scorer(&searcher.segment_readers()[0], 1.0f32)
                 .unwrap();
             range_scorer
         };

src/query/range_query/range_query_fastfield.rs

@@ -52,12 +52,7 @@ impl FastFieldRangeWeight {
 }
 
 impl Weight for FastFieldRangeWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
         // Check if both bounds are Bound::Unbounded
         if self.bounds.is_unbounded() {
             return Ok(Box::new(AllScorer::new(reader.max_doc())));
@@ -114,21 +109,11 @@ impl Weight for FastFieldRangeWeight {
                     else {
                         return Ok(Box::new(EmptyScorer));
                     };
-                    search_on_u64_ff(
+                    search_on_u64_ff(column, boost, BoundsRange::new(lower_bound, upper_bound))
-                        column,
+                }
-                        boost,
+                Type::U64 | Type::I64 | Type::F64 => {
-                        BoundsRange::new(lower_bound, upper_bound),
+                    search_on_json_numerical_field(reader, &field_name, typ, bounds, boost)
-                        seek_doc,
-                    )
                 }
-                Type::U64 | Type::I64 | Type::F64 => search_on_json_numerical_field(
-                    reader,
-                    &field_name,
-                    typ,
-                    bounds,
-                    boost,
-                    seek_doc,
-                ),
                 Type::Date => {
                     let fast_field_reader = reader.fast_fields();
                     let Some((column, _col_type)) = fast_field_reader
@@ -141,7 +126,6 @@ impl Weight for FastFieldRangeWeight {
                         column,
                         boost,
                         BoundsRange::new(bounds.lower_bound, bounds.upper_bound),
-                        seek_doc,
                     )
                 }
                 Type::Bool | Type::Facet | Type::Bytes | Type::Json | Type::IpAddr => {
@@ -170,7 +154,7 @@ impl Weight for FastFieldRangeWeight {
                 ip_addr_column.min_value(),
                 ip_addr_column.max_value(),
             );
-            let docset = RangeDocSet::new(value_range, ip_addr_column, seek_doc);
+            let docset = RangeDocSet::new(value_range, ip_addr_column);
             Ok(Box::new(ConstScorer::new(docset, boost)))
         } else if field_type.is_str() {
             let Some(str_dict_column): Option<StrColumn> = reader.fast_fields().str(&field_name)?
@@ -189,12 +173,7 @@ impl Weight for FastFieldRangeWeight {
             else {
                 return Ok(Box::new(EmptyScorer));
             };
-            search_on_u64_ff(
+            search_on_u64_ff(column, boost, BoundsRange::new(lower_bound, upper_bound))
-                column,
-                boost,
-                BoundsRange::new(lower_bound, upper_bound),
-                seek_doc,
-            )
         } else {
             assert!(
                 maps_to_u64_fastfield(field_type.value_type()),
@@ -236,13 +215,12 @@ impl Weight for FastFieldRangeWeight {
                 column,
                 boost,
                 BoundsRange::new(bounds.lower_bound, bounds.upper_bound),
-                seek_doc,
             )
         }
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         if scorer.seek(doc) != doc {
             return Err(TantivyError::InvalidArgument(format!(
                 "Document #({doc}) does not match"
@@ -252,10 +230,6 @@ impl Weight for FastFieldRangeWeight {
 
         Ok(explanation)
     }
-
-    fn intersection_priority(&self) -> u32 {
-        30u32
-    }
 }
 
 /// On numerical fields the column type may not match the user provided one.
@@ -267,7 +241,6 @@ fn search_on_json_numerical_field(
     typ: Type,
     bounds: BoundsRange<ValueBytes<Vec<u8>>>,
     boost: Score,
-    seek_doc: DocId,
 ) -> crate::Result<Box<dyn Scorer>> {
     // Since we don't know which type was interpolated for the internal column we
     // have to check for all numeric types (only one exists)
@@ -345,7 +318,6 @@ fn search_on_json_numerical_field(
         column,
         boost,
         BoundsRange::new(bounds.lower_bound, bounds.upper_bound),
-        seek_doc,
     )
 }
 
@@ -424,7 +396,6 @@ fn search_on_u64_ff(
     column: Column<u64>,
     boost: Score,
     bounds: BoundsRange<u64>,
-    seek_doc: DocId,
 ) -> crate::Result<Box<dyn Scorer>> {
     let col_min_value = column.min_value();
     let col_max_value = column.max_value();
@@ -455,8 +426,8 @@ fn search_on_u64_ff(
         }
     }
 
-    let doc_set = RangeDocSet::new(value_range, column, seek_doc);
+    let docset = RangeDocSet::new(value_range, column);
-    Ok(Box::new(ConstScorer::new(doc_set, boost)))
+    Ok(Box::new(ConstScorer::new(docset, boost)))
 }
 
 /// Returns true if the type maps to a u64 fast field
@@ -533,7 +504,7 @@ mod tests {
         DateOptions, Field, NumericOptions, Schema, SchemaBuilder, FAST, INDEXED, STORED, STRING,
         TEXT,
     };
-    use crate::{DocId, Index, IndexWriter, TantivyDocument, Term, TERMINATED};
+    use crate::{Index, IndexWriter, TantivyDocument, Term, TERMINATED};
 
     #[test]
     fn test_text_field_ff_range_query() -> crate::Result<()> {
@@ -1171,52 +1142,11 @@ mod tests {
             Bound::Included(Term::from_field_u64(field, 50_002)),
         ));
         let scorer = range_query
-            .scorer(searcher.segment_reader(0), 1.0f32, 0)
+            .scorer(searcher.segment_reader(0), 1.0f32)
             .unwrap();
         assert_eq!(scorer.doc(), TERMINATED);
     }
 
-    #[test]
-    fn test_fastfield_range_weight_seek_doc() {
-        let mut schema_builder = SchemaBuilder::new();
-        let field = schema_builder.add_u64_field("value", FAST);
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut writer: IndexWriter = index.writer_for_tests().unwrap();
-
-        // Create 20 documents with values
-        //  0, 10, 20, ..., 90
-        // and then 50  again.
-        for i in 0..10 {
-            writer.add_document(doc!(field => (i * 10) as u64)).unwrap();
-        }
-        writer.add_document(doc!(field => 50u64)).unwrap();
-        writer.commit().unwrap();
-
-        let searcher = index.reader().unwrap().searcher();
-        let segment_reader = searcher.segment_reader(0);
-
-        let range_weight = FastFieldRangeWeight::new(BoundsRange::new(
-            Bound::Included(Term::from_field_u64(field, 30)),
-            Bound::Included(Term::from_field_u64(field, 70)),
-        ));
-
-        let doc_when_seeking_from = |seek_from: DocId| {
-            let doc_set = range_weight
-                .scorer(segment_reader, 1.0f32, seek_from)
-                .unwrap();
-            crate::docset::docset_to_doc_vec(doc_set)
-        };
-
-        assert_eq!(doc_when_seeking_from(0), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(1), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(3), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(7), vec![7, 10]);
-        assert_eq!(doc_when_seeking_from(8), vec![10]);
-        assert_eq!(doc_when_seeking_from(10), vec![10]);
-        assert_eq!(doc_when_seeking_from(11), Vec::<DocId>::new());
-    }
-
     #[test]
     fn range_regression3_test() {
         let ops = vec![doc_from_id_1(1), doc_from_id_1(2), doc_from_id_1(3)];

src/query/reqopt_scorer.rs

@@ -81,6 +81,7 @@ where
     TOptScorer: Scorer,
     TScoreCombiner: ScoreCombiner,
 {
+    #[inline]
     fn score(&mut self) -> Score {
         if let Some(score) = self.score_cache {
             return score;

src/query/score_combiner.rs

@@ -29,6 +29,7 @@ impl ScoreCombiner for DoNothingCombiner {
 
     fn clear(&mut self) {}
 
+    #[inline]
     fn score(&self) -> Score {
         1.0
     }
@@ -49,6 +50,7 @@ impl ScoreCombiner for SumCombiner {
         self.score = 0.0;
     }
 
+    #[inline]
     fn score(&self) -> Score {
         self.score
     }
@@ -86,6 +88,7 @@ impl ScoreCombiner for DisjunctionMaxCombiner {
         self.sum = 0.0;
     }
 
+    #[inline]
     fn score(&self) -> Score {
         self.max + (self.sum - self.max) * self.tie_breaker
     }

src/query/scorer.rs

@@ -18,6 +18,7 @@ pub trait Scorer: downcast_rs::Downcast + DocSet + 'static {
 impl_downcast!(Scorer);
 
 impl Scorer for Box<dyn Scorer> {
+    #[inline]
     fn score(&mut self) -> Score {
         self.deref_mut().score()
     }

src/query/term_query/mod.rs

@@ -37,7 +37,7 @@ mod tests {
         );
         let term_weight = term_query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
         let segment_reader = searcher.segment_reader(0);
-        let mut term_scorer = term_weight.scorer(segment_reader, 1.0, 0)?;
+        let mut term_scorer = term_weight.scorer(segment_reader, 1.0)?;
         assert_eq!(term_scorer.doc(), 0);
         assert_nearly_equals!(term_scorer.score(), 0.28768212);
         Ok(())
@@ -65,7 +65,7 @@ mod tests {
         );
         let term_weight = term_query.weight(EnableScoring::enabled_from_searcher(&searcher))?;
         let segment_reader = searcher.segment_reader(0);
-        let mut term_scorer = term_weight.scorer(segment_reader, 1.0, 0)?;
+        let mut term_scorer = term_weight.scorer(segment_reader, 1.0)?;
         for i in 0u32..COMPRESSION_BLOCK_SIZE as u32 {
             assert_eq!(term_scorer.doc(), i);
             if i == COMPRESSION_BLOCK_SIZE as u32 - 1u32 {
@@ -162,7 +162,7 @@ mod tests {
         let searcher = index.reader()?.searcher();
         let term_weight =
             term_query.weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
-        let mut term_scorer = term_weight.scorer(searcher.segment_reader(0u32), 1.0, 0)?;
+        let mut term_scorer = term_weight.scorer(searcher.segment_reader(0u32), 1.0)?;
         assert_eq!(term_scorer.doc(), 0u32);
         term_scorer.seek(1u32);
         assert_eq!(term_scorer.doc(), 1u32);
@@ -470,7 +470,7 @@ mod tests {
                 .weight(EnableScoring::disabled_from_schema(&schema))
                 .unwrap();
             term_weight
-                .scorer(searcher.segment_reader(0u32), 1.0f32, 0)
+                .scorer(searcher.segment_reader(0u32), 1.0f32)
                 .unwrap()
         };
         // Should be an allscorer
@@ -484,53 +484,6 @@ mod tests {
         assert!(empty_scorer.is::<EmptyScorer>());
     }
 
-    #[test]
-    fn test_term_weight_seek_doc() -> crate::Result<()> {
-        let mut schema_builder = Schema::builder();
-        let text_field = schema_builder.add_text_field("text", TEXT);
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer: IndexWriter = index.writer_for_tests()?;
-
-        // Create 11 documents where docs 3, 4, 5, 6, 7, and 10 contain "target"
-        // (similar pattern to test_fastfield_range_weight_seek_doc)
-        for i in 0..11 {
-            if i == 3 || i == 4 || i == 5 || i == 6 || i == 7 || i == 10 {
-                index_writer.add_document(doc!(text_field => "target"))?;
-            } else {
-                index_writer.add_document(doc!(text_field => "other"))?;
-            }
-        }
-        index_writer.commit()?;
-
-        let searcher = index.reader()?.searcher();
-        let segment_reader = searcher.segment_reader(0);
-
-        let term_query = TermQuery::new(
-            Term::from_field_text(text_field, "target"),
-            IndexRecordOption::Basic,
-        );
-        let term_weight =
-            term_query.weight(EnableScoring::disabled_from_schema(searcher.schema()))?;
-
-        let doc_when_seeking_from = |seek_from: crate::DocId| {
-            let scorer = term_weight
-                .scorer(segment_reader, 1.0f32, seek_from)
-                .unwrap();
-            crate::docset::docset_to_doc_vec(scorer)
-        };
-
-        assert_eq!(doc_when_seeking_from(0), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(1), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(3), vec![3, 4, 5, 6, 7, 10]);
-        assert_eq!(doc_when_seeking_from(7), vec![7, 10]);
-        assert_eq!(doc_when_seeking_from(8), vec![10]);
-        assert_eq!(doc_when_seeking_from(10), vec![10]);
-        assert_eq!(doc_when_seeking_from(11), Vec::<crate::DocId>::new());
-
-        Ok(())
-    }
-
     #[test]
     fn test_term_weight_all_query_optimization_disable_when_scoring_enabled() {
         let mut schema_builder = Schema::builder();
@@ -556,7 +509,7 @@ mod tests {
                 .weight(EnableScoring::enabled_from_searcher(&searcher))
                 .unwrap();
             term_weight
-                .scorer(searcher.segment_reader(0u32), 1.0f32, 0)
+                .scorer(searcher.segment_reader(0u32), 1.0f32)
                 .unwrap()
         };
         // Should be an allscorer

src/query/term_query/term_scorer.rs

@@ -119,6 +119,7 @@ impl DocSet for TermScorer {
 }
 
 impl Scorer for TermScorer {
+    #[inline]
     fn score(&mut self) -> Score {
         let fieldnorm_id = self.fieldnorm_id();
         let term_freq = self.term_freq();

src/query/term_query/term_weight.rs

@@ -34,19 +34,12 @@ impl TermOrEmptyOrAllScorer {
 }
 
 impl Weight for TermWeight {
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>> {
-        &self,
+        Ok(self.specialized_scorer(reader, boost)?.into_boxed_scorer())
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>> {
-        Ok(self
-            .specialized_scorer(reader, boost, seek_doc)?
-            .into_boxed_scorer())
     }
 
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation> {
-        match self.specialized_scorer(reader, 1.0, doc)? {
+        match self.specialized_scorer(reader, 1.0)? {
             TermOrEmptyOrAllScorer::TermScorer(mut term_scorer) => {
                 if term_scorer.doc() > doc || term_scorer.seek(doc) != doc {
                     return Err(does_not_match(doc));
@@ -62,7 +55,7 @@ impl Weight for TermWeight {
 
     fn count(&self, reader: &SegmentReader) -> crate::Result<u32> {
         if let Some(alive_bitset) = reader.alive_bitset() {
-            Ok(self.scorer(reader, 1.0, 0)?.count(alive_bitset))
+            Ok(self.scorer(reader, 1.0)?.count(alive_bitset))
         } else {
             let field = self.term.field();
             let inv_index = reader.inverted_index(field)?;
@@ -78,7 +71,7 @@ impl Weight for TermWeight {
         reader: &SegmentReader,
         callback: &mut dyn FnMut(DocId, Score),
     ) -> crate::Result<()> {
-        match self.specialized_scorer(reader, 1.0, 0u32)? {
+        match self.specialized_scorer(reader, 1.0)? {
             TermOrEmptyOrAllScorer::TermScorer(mut term_scorer) => {
                 for_each_scorer(&mut *term_scorer, callback);
             }
@@ -97,7 +90,7 @@ impl Weight for TermWeight {
         reader: &SegmentReader,
         callback: &mut dyn FnMut(&[DocId]),
     ) -> crate::Result<()> {
-        match self.specialized_scorer(reader, 1.0, 0u32)? {
+        match self.specialized_scorer(reader, 1.0)? {
             TermOrEmptyOrAllScorer::TermScorer(mut term_scorer) => {
                 let mut buffer = [0u32; COLLECT_BLOCK_BUFFER_LEN];
                 for_each_docset_buffered(&mut term_scorer, &mut buffer, callback);
@@ -128,7 +121,7 @@ impl Weight for TermWeight {
         reader: &SegmentReader,
         callback: &mut dyn FnMut(DocId, Score) -> Score,
     ) -> crate::Result<()> {
-        let specialized_scorer = self.specialized_scorer(reader, 1.0, 0u32)?;
+        let specialized_scorer = self.specialized_scorer(reader, 1.0)?;
         match specialized_scorer {
             TermOrEmptyOrAllScorer::TermScorer(term_scorer) => {
                 crate::query::boolean_query::block_wand_single_scorer(
@@ -146,12 +139,6 @@ impl Weight for TermWeight {
         }
         Ok(())
     }
-
-    /// Returns a priority number used to sort weights when running an
-    /// intersection.
-    fn intersection_priority(&self) -> u32 {
-        10u32
-    }
 }
 
 impl TermWeight {
@@ -182,7 +169,7 @@ impl TermWeight {
         reader: &SegmentReader,
         boost: Score,
     ) -> crate::Result<Option<TermScorer>> {
-        let scorer = self.specialized_scorer(reader, boost, 0u32)?;
+        let scorer = self.specialized_scorer(reader, boost)?;
         Ok(match scorer {
             TermOrEmptyOrAllScorer::TermScorer(scorer) => Some(*scorer),
             _ => None,
@@ -193,7 +180,6 @@ impl TermWeight {
         &self,
         reader: &SegmentReader,
         boost: Score,
-        seek_doc: DocId,
     ) -> crate::Result<TermOrEmptyOrAllScorer> {
         let field = self.term.field();
         let inverted_index = reader.inverted_index(field)?;
@@ -210,11 +196,8 @@ impl TermWeight {
             )));
         }
 
-        let segment_postings: SegmentPostings = inverted_index.read_postings_from_terminfo(
+        let segment_postings: SegmentPostings =
-            &term_info,
+            inverted_index.read_postings_from_terminfo(&term_info, self.index_record_option)?;
-            self.index_record_option,
-            seek_doc,
-        )?;
 
         let fieldnorm_reader = self.fieldnorm_reader(reader)?;
         let similarity_weight = self.similarity_weight.boost_by(boost);

src/query/union/buffered_union.rs

@@ -128,6 +128,7 @@ impl<TScorer: Scorer, TScoreCombiner: ScoreCombiner> BufferedUnionScorer<TScorer
         }
     }
 
+    #[inline]
     fn advance_buffered(&mut self) -> bool {
         while self.bucket_idx < HORIZON_NUM_TINYBITSETS {
             if let Some(val) = self.bitsets[self.bucket_idx].pop_lowest() {
@@ -156,6 +157,7 @@ where
     TScorer: Scorer,
     TScoreCombiner: ScoreCombiner,
 {
+    #[inline]
     fn advance(&mut self) -> DocId {
         if self.advance_buffered() {
             return self.doc;
@@ -245,6 +247,7 @@ where
         }
     }
 
+    #[inline]
     fn doc(&self) -> DocId {
         self.doc
     }
@@ -286,6 +289,7 @@ where
     TScoreCombiner: ScoreCombiner,
     TScorer: Scorer,
 {
+    #[inline]
     fn score(&mut self) -> Score {
         self.score
     }

src/query/weight.rs

@@ -68,28 +68,15 @@ pub trait Weight: Send + Sync + 'static {
     ///
     /// `boost` is a multiplier to apply to the score.
     ///
-    /// As an optimization, the scorer can be positioned on any document below `seek_doc`
-    /// matching the request.
-    /// If there are no such document, it should match the first document matching the request;
-    /// (or TERMINATED if no documents match).
-    ///
-    /// Entirely ignoring that parameter and positionning the Scorer on the first document
-    /// is always correct.
-    ///
     /// See [`Query`](crate::query::Query).
-    fn scorer(
+    fn scorer(&self, reader: &SegmentReader, boost: Score) -> crate::Result<Box<dyn Scorer>>;
-        &self,
-        reader: &SegmentReader,
-        boost: Score,
-        seek_doc: DocId,
-    ) -> crate::Result<Box<dyn Scorer>>;
 
     /// Returns an [`Explanation`] for the given document.
     fn explain(&self, reader: &SegmentReader, doc: DocId) -> crate::Result<Explanation>;
 
     /// Returns the number documents within the given [`SegmentReader`].
     fn count(&self, reader: &SegmentReader) -> crate::Result<u32> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         if let Some(alive_bitset) = reader.alive_bitset() {
             Ok(scorer.count(alive_bitset))
         } else {
@@ -104,7 +91,7 @@ pub trait Weight: Send + Sync + 'static {
         reader: &SegmentReader,
         callback: &mut dyn FnMut(DocId, Score),
     ) -> crate::Result<()> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         for_each_scorer(scorer.as_mut(), callback);
         Ok(())
     }
@@ -116,7 +103,7 @@ pub trait Weight: Send + Sync + 'static {
         reader: &SegmentReader,
         callback: &mut dyn FnMut(&[DocId]),
     ) -> crate::Result<()> {
-        let mut docset = self.scorer(reader, 1.0, 0)?;
+        let mut docset = self.scorer(reader, 1.0)?;
 
         let mut buffer = [0u32; COLLECT_BLOCK_BUFFER_LEN];
         for_each_docset_buffered(&mut docset, &mut buffer, callback);
@@ -139,18 +126,8 @@ pub trait Weight: Send + Sync + 'static {
         reader: &SegmentReader,
         callback: &mut dyn FnMut(DocId, Score) -> Score,
     ) -> crate::Result<()> {
-        let mut scorer = self.scorer(reader, 1.0, 0)?;
+        let mut scorer = self.scorer(reader, 1.0)?;
         for_each_pruning_scorer(scorer.as_mut(), threshold, callback);
         Ok(())
     }
-
-    /// Returns a priority number used to sort weights when running an
-    /// intersection.
-    ///
-    /// Tweaking this value only impacts performance.
-    /// A higher priority means that the `.scorer()` will be more likely to be evaluated
-    /// after the sibling weights, and be passed a higher `seek_doc` value as a result.
-    fn intersection_priority(&self) -> u32 {
-        20u32
-    }
 }

src/schema/document/owned_value.rs

@@ -58,6 +58,31 @@ impl AsRef<OwnedValue> for OwnedValue {
     }
 }
 
+impl OwnedValue {
+    /// Returns a u8 discriminant value for the `OwnedValue` variant.
+    ///
+    /// This can be used to sort `OwnedValue` instances by their type.
+    pub fn discriminant_value(&self) -> u8 {
+        match self {
+            OwnedValue::Null => 0,
+            OwnedValue::Str(_) => 1,
+            OwnedValue::PreTokStr(_) => 2,
+            // It is key to make sure U64, I64, F64 are grouped together in there, otherwise we
+            // might be breaking transivity.
+            OwnedValue::U64(_) => 3,
+            OwnedValue::I64(_) => 4,
+            OwnedValue::F64(_) => 5,
+            OwnedValue::Bool(_) => 6,
+            OwnedValue::Date(_) => 7,
+            OwnedValue::Facet(_) => 8,
+            OwnedValue::Bytes(_) => 9,
+            OwnedValue::Array(_) => 10,
+            OwnedValue::Object(_) => 11,
+            OwnedValue::IpAddr(_) => 12,
+        }
+    }
+}
+
 impl<'a> Value<'a> for &'a OwnedValue {
     type ArrayIter = std::slice::Iter<'a, OwnedValue>;
     type ObjectIter = ObjectMapIter<'a>;

src/schema/mod.rs

@@ -98,6 +98,10 @@
 //! make it possible to access the value given the doc id rapidly. This is useful if the value
 //! of the field is required during scoring or collection for instance.
 //!
+//! Some queries may leverage Fast fields when run on a field that is not indexed. This can be
+//! handy if that kind of request is infrequent, however note that searching on a Fast field is
+//! generally much slower than searching in an index.
+//!
 //! ```
 //! use tantivy::schema::*;
 //! let mut schema_builder = Schema::builder();

src/snippet/mod.rs

@@ -483,7 +483,7 @@ mod tests {
 
     use super::{collapse_overlapped_ranges, search_fragments, select_best_fragment_combination};
     use crate::query::QueryParser;
-    use crate::schema::{IndexRecordOption, Schema, TextFieldIndexing, TextOptions, TEXT};
+    use crate::schema::{Schema, TEXT};
     use crate::snippet::SnippetGenerator;
     use crate::tokenizer::{NgramTokenizer, SimpleTokenizer};
     use crate::Index;
@@ -727,8 +727,10 @@ Survey in 2016, 2017, and 2018."#;
         Ok(())
     }
 
+    #[cfg(feature = "stemmer")]
     #[test]
     fn test_snippet_generator() -> crate::Result<()> {
+        use crate::schema::{IndexRecordOption, TextFieldIndexing, TextOptions};
         let mut schema_builder = Schema::builder();
         let text_options = TextOptions::default().set_indexing_options(
             TextFieldIndexing::default()

src/store/mod.rs

@@ -102,6 +102,7 @@ pub(crate) mod tests {
     }
 
     const NUM_DOCS: usize = 1_000;
+
     #[test]
     fn test_doc_store_iter_with_delete_bug_1077() -> crate::Result<()> {
         // this will cover deletion of the first element in a checkpoint
@@ -113,7 +114,7 @@ pub(crate) mod tests {
         let directory = RamDirectory::create();
         let store_wrt = directory.open_write(path)?;
         let schema =
-            write_lorem_ipsum_store(store_wrt, NUM_DOCS, Compressor::Lz4, BLOCK_SIZE, true);
+            write_lorem_ipsum_store(store_wrt, NUM_DOCS, Compressor::default(), BLOCK_SIZE, true);
         let field_title = schema.get_field("title").unwrap();
         let store_file = directory.open_read(path)?;
         let store = StoreReader::open(store_file, 10)?;

src/store/reader.rs

@@ -465,7 +465,7 @@ mod tests {
         let directory = RamDirectory::create();
         let path = Path::new("store");
         let writer = directory.open_write(path)?;
-        let schema = write_lorem_ipsum_store(writer, 500, Compressor::default(), BLOCK_SIZE, true);
+        let schema = write_lorem_ipsum_store(writer, 500, Compressor::None, BLOCK_SIZE, true);
         let title = schema.get_field("title").unwrap();
         let store_file = directory.open_read(path)?;
         let store = StoreReader::open(store_file, DOCSTORE_CACHE_CAPACITY)?;
@@ -499,7 +499,7 @@ mod tests {
         assert_eq!(store.cache_stats().cache_hits, 1);
         assert_eq!(store.cache_stats().cache_misses, 2);
 
-        assert_eq!(store.cache.peek_lru(), Some(11207));
+        assert_eq!(store.cache.peek_lru(), Some(232206));
 
         Ok(())
     }

src/tokenizer/mod.rs

@@ -132,13 +132,14 @@ mod regex_tokenizer;
 mod remove_long;
 mod simple_tokenizer;
 mod split_compound_words;
-mod stemmer;
 mod stop_word_filter;
 mod tokenized_string;
 mod tokenizer;
 mod tokenizer_manager;
 mod whitespace_tokenizer;
 
+#[cfg(feature = "stemmer")]
+mod stemmer;
 pub use tokenizer_api::{BoxTokenStream, Token, TokenFilter, TokenStream, Tokenizer};
 
 pub use self::alphanum_only::AlphaNumOnlyFilter;
@@ -151,6 +152,7 @@ pub use self::regex_tokenizer::RegexTokenizer;
 pub use self::remove_long::RemoveLongFilter;
 pub use self::simple_tokenizer::{SimpleTokenStream, SimpleTokenizer};
 pub use self::split_compound_words::SplitCompoundWords;
+#[cfg(feature = "stemmer")]
 pub use self::stemmer::{Language, Stemmer};
 pub use self::stop_word_filter::StopWordFilter;
 pub use self::tokenized_string::{PreTokenizedStream, PreTokenizedString};
@@ -167,10 +169,7 @@ pub const MAX_TOKEN_LEN: usize = u16::MAX as usize - 5;
 
 #[cfg(test)]
 pub(crate) mod tests {
-    use super::{
+    use super::{Token, TokenizerManager};
-        Language, LowerCaser, RemoveLongFilter, SimpleTokenizer, Stemmer, Token, TokenizerManager,
-    };
-    use crate::tokenizer::TextAnalyzer;
 
     /// This is a function that can be used in tests and doc tests
     /// to assert a token's correctness.
@@ -205,59 +204,15 @@ pub(crate) mod tests {
     }
 
     #[test]
-    fn test_en_tokenizer() {
+    fn test_tokenizer_does_not_exist() {
         let tokenizer_manager = TokenizerManager::default();
         assert!(tokenizer_manager.get("en_doesnotexist").is_none());
-        let mut en_tokenizer = tokenizer_manager.get("en_stem").unwrap();
-        let mut tokens: Vec<Token> = vec![];
-        {
-            let mut add_token = |token: &Token| {
-                tokens.push(token.clone());
-            };
-            en_tokenizer
-                .token_stream("Hello, happy tax payer!")
-                .process(&mut add_token);
-        }
-
-        assert_eq!(tokens.len(), 4);
-        assert_token(&tokens[0], 0, "hello", 0, 5);
-        assert_token(&tokens[1], 1, "happi", 7, 12);
-        assert_token(&tokens[2], 2, "tax", 13, 16);
-        assert_token(&tokens[3], 3, "payer", 17, 22);
-    }
-
-    #[test]
-    fn test_non_en_tokenizer() {
-        let tokenizer_manager = TokenizerManager::default();
-        tokenizer_manager.register(
-            "el_stem",
-            TextAnalyzer::builder(SimpleTokenizer::default())
-                .filter(RemoveLongFilter::limit(40))
-                .filter(LowerCaser)
-                .filter(Stemmer::new(Language::Greek))
-                .build(),
-        );
-        let mut en_tokenizer = tokenizer_manager.get("el_stem").unwrap();
-        let mut tokens: Vec<Token> = vec![];
-        {
-            let mut add_token = |token: &Token| {
-                tokens.push(token.clone());
-            };
-            en_tokenizer
-                .token_stream("Καλημέρα, χαρούμενε φορολογούμενε!")
-                .process(&mut add_token);
-        }
-
-        assert_eq!(tokens.len(), 3);
-        assert_token(&tokens[0], 0, "καλημερ", 0, 16);
-        assert_token(&tokens[1], 1, "χαρουμεν", 18, 36);
-        assert_token(&tokens[2], 2, "φορολογουμεν", 37, 63);
     }
 
     #[test]
     fn test_tokenizer_empty() {
         let tokenizer_manager = TokenizerManager::default();
-        let mut en_tokenizer = tokenizer_manager.get("en_stem").unwrap();
+        let mut en_tokenizer = tokenizer_manager.get("default").unwrap();
         {
             let mut tokens: Vec<Token> = vec![];
             {

src/tokenizer/stemmer.rs

@@ -142,3 +142,60 @@ impl<T: TokenStream> TokenStream for StemmerTokenStream<T> {
         self.tail.token_mut()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use tokenizer_api::Token;
+
+    use super::*;
+    use crate::tokenizer::tests::assert_token;
+    use crate::tokenizer::{LowerCaser, SimpleTokenizer, TextAnalyzer, TokenizerManager};
+
+    #[test]
+    fn test_en_stem() {
+        let tokenizer_manager = TokenizerManager::default();
+        let mut en_tokenizer = tokenizer_manager.get("en_stem").unwrap();
+        let mut tokens: Vec<Token> = vec![];
+        {
+            let mut add_token = |token: &Token| {
+                tokens.push(token.clone());
+            };
+            en_tokenizer
+                .token_stream("Dogs are the bests!")
+                .process(&mut add_token);
+        }
+
+        assert_eq!(tokens.len(), 4);
+        assert_token(&tokens[0], 0, "dog", 0, 4);
+        assert_token(&tokens[1], 1, "are", 5, 8);
+        assert_token(&tokens[2], 2, "the", 9, 12);
+        assert_token(&tokens[3], 3, "best", 13, 18);
+    }
+
+    #[test]
+    fn test_non_en_stem() {
+        let tokenizer_manager = TokenizerManager::default();
+        tokenizer_manager.register(
+            "el_stem",
+            TextAnalyzer::builder(SimpleTokenizer::default())
+                .filter(LowerCaser)
+                .filter(Stemmer::new(Language::Greek))
+                .build(),
+        );
+        let mut el_tokenizer = tokenizer_manager.get("el_stem").unwrap();
+        let mut tokens: Vec<Token> = vec![];
+        {
+            let mut add_token = |token: &Token| {
+                tokens.push(token.clone());
+            };
+            el_tokenizer
+                .token_stream("Καλημέρα, χαρούμενε φορολογούμενε!")
+                .process(&mut add_token);
+        }
+
+        assert_eq!(tokens.len(), 3);
+        assert_token(&tokens[0], 0, "καλημερ", 0, 16);
+        assert_token(&tokens[1], 1, "χαρουμεν", 18, 36);
+        assert_token(&tokens[2], 2, "φορολογουμεν", 37, 63);
+    }
+}

src/tokenizer/tokenizer_manager.rs

@@ -1,10 +1,9 @@
 use std::collections::HashMap;
 use std::sync::{Arc, RwLock};
 
-use crate::tokenizer::stemmer::Language;
 use crate::tokenizer::tokenizer::TextAnalyzer;
 use crate::tokenizer::{
-    LowerCaser, RawTokenizer, RemoveLongFilter, SimpleTokenizer, Stemmer, WhitespaceTokenizer,
+    LowerCaser, RawTokenizer, RemoveLongFilter, SimpleTokenizer, WhitespaceTokenizer,
 };
 
 /// The tokenizer manager serves as a store for
@@ -64,14 +63,18 @@ impl Default for TokenizerManager {
                 .filter(LowerCaser)
                 .build(),
         );
-        manager.register(
+        #[cfg(feature = "stemmer")]
-            "en_stem",
+        {
-            TextAnalyzer::builder(SimpleTokenizer::default())
+            use crate::tokenizer::stemmer::{Language, Stemmer};
-                .filter(RemoveLongFilter::limit(40))
+            manager.register(
-                .filter(LowerCaser)
+                "en_stem",
-                .filter(Stemmer::new(Language::English))
+                TextAnalyzer::builder(SimpleTokenizer::default())
-                .build(),
+                    .filter(RemoveLongFilter::limit(40))
-        );
+                    .filter(LowerCaser) // The stemmer does not lowercase
+                    .filter(Stemmer::new(Language::English))
+                    .build(),
+            );
+        }
         manager.register("whitespace", WhitespaceTokenizer::default());
         manager
     }