From 9b61a7167c3ed115eb89105279e6cdef6efad8d4 Mon Sep 17 00:00:00 2001
From: Ruihang Xia <waynestxia@gmail.com>
Date: Tue, 3 Mar 2026 07:08:27 +0800
Subject: [PATCH] resolve tiny cr comments

Signed-off-by: Ruihang Xia <waynestxia@gmail.com>
---
 src/mito2/src/cache/index/result_cache.rs |  6 ++++--
 src/mito2/src/read/scan_util.rs           | 16 ++++++++++++++++
 src/mito2/src/sst/parquet/reader.rs       | 19 +++++++++++++++----
 3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/src/mito2/src/cache/index/result_cache.rs b/src/mito2/src/cache/index/result_cache.rs
index d4a62f573d..dfed662a14 100644
--- a/src/mito2/src/cache/index/result_cache.rs
+++ b/src/mito2/src/cache/index/result_cache.rs
@@ -258,8 +258,10 @@ pub struct MinMaxKey {
 
 impl MinMaxKey {
     pub fn new(exprs: Arc<Vec<String>>, schema_version: u64, skip_fields: bool) -> Self {
-        let mem_usage =
-            exprs.iter().map(|s| s.len()).sum::<usize>() + size_of::<u64>() + size_of::<bool>();
+        let mem_usage = size_of::<Self>()
+            + size_of::<Vec<String>>()
+            + exprs.len() * size_of::<String>()
+            + exprs.iter().map(|s| s.len()).sum::<usize>();
         Self {
             exprs,
             schema_version,
diff --git a/src/mito2/src/read/scan_util.rs b/src/mito2/src/read/scan_util.rs
index a1bd055242..1d970d7bd0 100644
--- a/src/mito2/src/read/scan_util.rs
+++ b/src/mito2/src/read/scan_util.rs
@@ -182,6 +182,10 @@ pub(crate) struct ScanMetricsSet {
     bloom_filter_cache_hit: usize,
     /// Number of index result cache misses for bloom filter index.
     bloom_filter_cache_miss: usize,
+    /// Number of index result cache hits for minmax pruning.
+    minmax_cache_hit: usize,
+    /// Number of index result cache misses for minmax pruning.
+    minmax_cache_miss: usize,
     /// Number of pruner builder cache hits.
     pruner_cache_hit: usize,
     /// Number of pruner builder cache misses.
@@ -308,6 +312,8 @@ impl fmt::Debug for ScanMetricsSet {
             inverted_index_cache_miss,
             bloom_filter_cache_hit,
             bloom_filter_cache_miss,
+            minmax_cache_hit,
+            minmax_cache_miss,
             pruner_cache_hit,
             pruner_cache_miss,
             pruner_prune_cost,
@@ -433,6 +439,12 @@ impl fmt::Debug for ScanMetricsSet {
         if *bloom_filter_cache_miss > 0 {
             write!(f, ", \"bloom_filter_cache_miss\":{bloom_filter_cache_miss}")?;
         }
+        if *minmax_cache_hit > 0 {
+            write!(f, ", \"minmax_cache_hit\":{minmax_cache_hit}")?;
+        }
+        if *minmax_cache_miss > 0 {
+            write!(f, ", \"minmax_cache_miss\":{minmax_cache_miss}")?;
+        }
         if *pruner_cache_hit > 0 {
             write!(f, ", \"pruner_cache_hit\":{pruner_cache_hit}")?;
         }
@@ -639,6 +651,8 @@ impl ScanMetricsSet {
                     inverted_index_cache_miss,
                     bloom_filter_cache_hit,
                     bloom_filter_cache_miss,
+                    minmax_cache_hit,
+                    minmax_cache_miss,
                     pruner_cache_hit,
                     pruner_cache_miss,
                     pruner_prune_cost,
@@ -680,6 +694,8 @@ impl ScanMetricsSet {
         self.inverted_index_cache_miss += *inverted_index_cache_miss;
         self.bloom_filter_cache_hit += *bloom_filter_cache_hit;
         self.bloom_filter_cache_miss += *bloom_filter_cache_miss;
+        self.minmax_cache_hit += *minmax_cache_hit;
+        self.minmax_cache_miss += *minmax_cache_miss;
         self.pruner_cache_hit += *pruner_cache_hit;
         self.pruner_cache_miss += *pruner_cache_miss;
         self.pruner_prune_cost += *pruner_prune_cost;
diff --git a/src/mito2/src/sst/parquet/reader.rs b/src/mito2/src/sst/parquet/reader.rs
index 794007c1a4..73322b85c9 100644
--- a/src/mito2/src/sst/parquet/reader.rs
+++ b/src/mito2/src/sst/parquet/reader.rs
@@ -1177,11 +1177,16 @@ impl ParquetReaderBuilder {
 
         if let Some(index_result_cache) = index_result_cache
             && let Some(predicate_key) = cached_minmax_key.as_ref()
-            && let Some(result) = index_result_cache.get(predicate_key, file_id)
         {
-            let num_row_groups = parquet_meta.num_row_groups();
-            metrics.rg_minmax_filtered += num_row_groups.saturating_sub(result.row_group_count());
-            return (*result).clone();
+            if let Some(result) = index_result_cache.get(predicate_key, file_id) {
+                metrics.minmax_cache_hit += 1;
+                let num_row_groups = parquet_meta.num_row_groups();
+                metrics.rg_minmax_filtered +=
+                    num_row_groups.saturating_sub(result.row_group_count());
+                return (*result).clone();
+            }
+
+            metrics.minmax_cache_miss += 1;
         }
 
         let region_meta = read_format.metadata();
@@ -1334,6 +1339,10 @@ pub(crate) struct ReaderFilterMetrics {
     pub(crate) bloom_filter_cache_hit: usize,
     /// Number of index result cache misses for bloom filter index.
     pub(crate) bloom_filter_cache_miss: usize,
+    /// Number of index result cache hits for minmax pruning.
+    pub(crate) minmax_cache_hit: usize,
+    /// Number of index result cache misses for minmax pruning.
+    pub(crate) minmax_cache_miss: usize,
 
     /// Optional metrics for inverted index applier.
     pub(crate) inverted_index_apply_metrics: Option<InvertedIndexApplyMetrics>,
@@ -1374,6 +1383,8 @@ impl ReaderFilterMetrics {
         self.inverted_index_cache_miss += other.inverted_index_cache_miss;
         self.bloom_filter_cache_hit += other.bloom_filter_cache_hit;
         self.bloom_filter_cache_miss += other.bloom_filter_cache_miss;
+        self.minmax_cache_hit += other.minmax_cache_hit;
+        self.minmax_cache_miss += other.minmax_cache_miss;
 
         self.pruner_cache_hit += other.pruner_cache_hit;
         self.pruner_cache_miss += other.pruner_cache_miss;