feat: track index?

Signed-off-by: discord9 <discord9@163.com>

src/mito2/src/access_layer.rs

@@ -37,7 +37,7 @@ use crate::error::{CleanDirSnafu, DeleteIndexSnafu, DeleteSstSnafu, OpenDalSnafu
 use crate::metrics::{COMPACTION_STAGE_ELAPSED, FLUSH_ELAPSED};
 use crate::read::{FlatSource, Source};
 use crate::region::options::IndexOptions;
-use crate::sst::file::{FileHandle, RegionFileId, RegionIndexId};
+use crate::sst::file::{FileHandle, RegionFileId, RegionIndexId, delete_index};
 use crate::sst::index::IndexerBuilderImpl;
 use crate::sst::index::intermediate::IntermediateManager;
 use crate::sst::index::puffin_manager::{PuffinManagerFactory, SstPuffinManager};

src/mito2/src/sst/file.rs

@@ -538,38 +538,89 @@ pub async fn delete_files(
     );
 
     for (file_id, index_version) in file_ids {
-        if let Some(write_cache) = cache_manager.as_ref().and_then(|cache| cache.write_cache()) {
-            // Removes index file from the cache.
-            if delete_index {
-                write_cache
-                    .remove(IndexKey::new(
-                        region_id,
-                        *file_id,
-                        FileType::Puffin(*index_version),
-                    ))
-                    .await;
-            }
+        purge_index_write_cache_stager(
+            region_id,
+            delete_index,
+            access_layer,
+            cache_manager,
+            file_id,
+            index_version,
+        )
+        .await;
+    }
+    Ok(())
+}
 
-            // Remove the SST file from the cache.
+/// Delete index file for a given SST file&index version.
+pub async fn delete_index(
+    region_id: RegionId,
+    file_id: FileId,
+    index_version: u64,
+    access_layer: &AccessLayerRef,
+    cache_manager: &Option<CacheManagerRef>,
+) -> crate::error::Result<()> {
+    if let Err(err) = access_layer
+        .delete_index(&RegionIndexId::new(
+            RegionFileId::new(region_id, file_id),
+            index_version,
+        ))
+        .await
+    {
+        error!(err; "Failed to delete index file for {}/{}.{}",
+            region_id, file_id, index_version);
+    }
+
+    purge_index_write_cache_stager(
+        region_id,
+        true,
+        access_layer,
+        cache_manager,
+        &file_id,
+        &index_version,
+    )
+    .await;
+
+    Ok(())
+}
+
+pub async fn purge_index_write_cache_stager(
+    region_id: RegionId,
+    delete_index: bool,
+    access_layer: &Arc<crate::access_layer::AccessLayer>,
+    cache_manager: &Option<Arc<crate::cache::CacheManager>>,
+    file_id: &FileId,
+    index_version: &u64,
+) {
+    if let Some(write_cache) = cache_manager.as_ref().and_then(|cache| cache.write_cache()) {
+        // Removes index file from the cache.
+        if delete_index {
             write_cache
-                .remove(IndexKey::new(region_id, *file_id, FileType::Parquet))
+                .remove(IndexKey::new(
+                    region_id,
+                    *file_id,
+                    FileType::Puffin(*index_version),
+                ))
                 .await;
         }
 
-        // Purges index content in the stager.
-        if let Err(e) = access_layer
-            .puffin_manager_factory()
-            .purge_stager(RegionIndexId::new(
-                RegionFileId::new(region_id, *file_id),
-                *index_version,
-            ))
-            .await
-        {
-            error!(e; "Failed to purge stager with index file, file_id: {}, index_version: {}, region: {}",
-                    file_id, index_version, region_id);
-        }
+        // Remove the SST file from the cache.
+        write_cache
+            .remove(IndexKey::new(region_id, *file_id, FileType::Parquet))
+            .await;
+    }
+
+    // Purges index content in the stager.
+    if let Err(e) = access_layer
+        .puffin_manager_factory()
+        .purge_stager(RegionIndexId::new(
+            RegionFileId::new(region_id, *file_id),
+            *index_version,
+        ))
+        .await
+    {
+        error!(e; "Failed to purge stager with index file, file_id: {}, index_version: {}, region: {}",
+                file_id, index_version, region_id);
     }
-    Ok(())
 }
 
 #[cfg(test)]

src/mito2/src/sst/file_purger.rs

@@ -16,15 +16,23 @@ use std::fmt;
 use std::sync::Arc;
 
 use common_telemetry::error;
+use dashmap::DashMap;
 use store_api::storage::IndexVersion;
 
 use crate::access_layer::AccessLayerRef;
 use crate::cache::CacheManagerRef;
 use crate::error::Result;
 use crate::schedule::scheduler::SchedulerRef;
-use crate::sst::file::{FileMeta, RegionIndexId, delete_files};
+use crate::sst::file::{FileMeta, RegionIndexId, delete_files, delete_index};
 use crate::sst::file_ref::FileReferenceManagerRef;
 
+/// Index file reference tracking information
+#[derive(Debug, Default)]
+struct IndexRefInfo {
+    ref_count: usize,
+    is_deleted: bool,
+}
+
 /// A worker to delete files in background.
 pub trait FilePurger: Send + Sync + fmt::Debug {
     /// Send a request to remove the file.
@@ -65,6 +73,8 @@ pub struct LocalFilePurger {
     scheduler: SchedulerRef,
     sst_layer: AccessLayerRef,
     cache_manager: Option<CacheManagerRef>,
+    /// Maps RegionIndexId to (ref_count, is_deleted) for index files
+    index_refs: Arc<DashMap<RegionIndexId, IndexRefInfo>>,
 }
 
 impl fmt::Debug for LocalFilePurger {
@@ -123,6 +133,7 @@ impl LocalFilePurger {
             scheduler,
             sst_layer,
             cache_manager,
+            index_refs: Arc::new(DashMap::new()),
         }
     }
 
@@ -131,6 +142,66 @@ impl LocalFilePurger {
         self.scheduler.stop(true).await
     }
 
+    /// Add a reference to an index file
+    pub fn add_index_reference(&self, index_id: RegionIndexId) {
+        self.index_refs
+            .entry(index_id)
+            .and_modify(|info| {
+                info.ref_count += 1;
+            })
+            .or_insert(IndexRefInfo {
+                ref_count: 1,
+                is_deleted: false,
+            });
+    }
+
+    /// Remove a reference to an index file, returns should_delete
+    pub fn remove_index_reference(&self, index_id: &RegionIndexId) -> bool {
+        let mut should_delete = false;
+
+        if let Some(mut info) = self.index_refs.get_mut(index_id) {
+            info.ref_count -= 1;
+            should_delete = info.is_deleted && info.ref_count == 0;
+
+            if info.ref_count == 0 {
+                // Remove from map if no more references
+                drop(info); // Release the lock before removing
+                self.index_refs.remove(index_id);
+            }
+        }
+
+        should_delete
+    }
+
+    /// Mark an index file as deleted (but don't actually delete yet)
+    pub fn mark_index_deleted(&self, index_id: &RegionIndexId) -> bool {
+        let should_delete;
+
+        if let Some(mut info) = self.index_refs.get_mut(index_id) {
+            info.is_deleted = true;
+            should_delete = info.ref_count == 0;
+
+            if should_delete {
+                // Remove from map if no references
+                drop(info); // Release the lock before removing
+                self.index_refs.remove(index_id);
+            }
+        } else {
+            // No references exist, can delete immediately
+            should_delete = true;
+        }
+
+        should_delete
+    }
+
+    /// Check and delete index if it's marked deleted and has no references
+    fn check_and_delete_index(&self, file_meta: FileMeta, index_version: IndexVersion) {
+        let index_id = RegionIndexId::new(file_meta.file_id(), index_version);
+        if self.mark_index_deleted(&index_id) {
+            self.delete_index(file_meta, index_version);
+        }
+    }
+
     /// Deletes the file(and it's index, if any) from cache and storage.
     fn delete_file(&self, file_meta: FileMeta) {
         let sst_layer = self.sst_layer.clone();
@@ -158,9 +229,18 @@ impl LocalFilePurger {
             return;
         }
         let sst_layer = self.sst_layer.clone();
+        let cache_manager = self.cache_manager.clone();
         if let Err(e) = self.scheduler.schedule(Box::pin(async move {
             let index_id = RegionIndexId::new(file_meta.file_id(), old_version);
-            if let Err(e) = sst_layer.delete_index(&index_id).await {
+            if let Err(e) = delete_index(
+                file_meta.region_id,
+                file_meta.file_id,
+                old_version,
+                &sst_layer,
+                &cache_manager,
+            )
+            .await
+            {
                 error!(e; "Failed to delete index {:?} from storage", index_id);
             }
         })) {
@@ -171,13 +251,34 @@ impl LocalFilePurger {
 
 impl FilePurger for LocalFilePurger {
     fn remove_file(&self, file_meta: FileMeta, is_delete: bool) {
+        // Release reference to current index version if it exists
+        if file_meta.exists_index() {
+            let index_id = RegionIndexId::new(file_meta.file_id(), file_meta.index_version);
+            let should_delete = self.remove_index_reference(&index_id);
+
+            // If this index was marked for deletion and ref count reached 0, delete it
+            if should_delete {
+                self.delete_index(file_meta.clone(), file_meta.index_version);
+            }
+        }
+
         if is_delete {
             self.delete_file(file_meta);
         }
     }
 
     fn update_index(&self, file_meta: FileMeta, old_version: IndexVersion) {
-        self.delete_index(file_meta, old_version);
+        // Mark old index as deleted, but only actually delete if no references
+        self.check_and_delete_index(file_meta, old_version);
+    }
+
+    fn new_file(&self, file_meta: &FileMeta) {
+        if file_meta.exists_index() {
+            self.add_index_reference(RegionIndexId::new(
+                file_meta.file_id(),
+                file_meta.index_version,
+            ));
+        }
     }
 }
 
@@ -363,4 +464,809 @@ mod tests {
         assert!(!object_store.exists(&path).await.unwrap());
         assert!(!object_store.exists(&index_path).await.unwrap());
     }
+
+    // Tests for Index Reference Counting Logic
+
+    #[tokio::test]
+    async fn test_add_index_reference() {
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-add-index-ref");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store,
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = LocalFilePurger::new(scheduler.clone(), layer, None);
+
+        // Test adding a new index reference
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+
+        file_purger.add_index_reference(index_id);
+
+        {
+            // Check that the reference was added
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 1);
+            assert!(!info.is_deleted);
+        }
+
+        // Test adding another reference to the same index
+        file_purger.add_index_reference(index_id);
+
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 2);
+            assert!(!info.is_deleted);
+        }
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn test_remove_index_reference() {
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-remove-index-ref");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store,
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = LocalFilePurger::new(scheduler.clone(), layer, None);
+
+        // Add an index reference first
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+        file_purger.add_index_reference(index_id);
+        file_purger.add_index_reference(index_id); // Add twice for ref_count = 2
+
+        // Remove one reference
+        let should_delete = file_purger.remove_index_reference(&index_id);
+        assert!(!should_delete); // Should not delete as ref_count is still 1
+
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 1);
+        } // info is dropped here
+
+        // Remove the second reference
+        let should_delete = file_purger.remove_index_reference(&index_id);
+        assert!(!should_delete); // Should not delete as is_deleted is false
+
+        // Index should be removed from map as ref_count is 0
+        assert!(file_purger.index_refs.get(&index_id).is_none());
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn test_remove_index_reference_with_deleted_flag() {
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-remove-index-ref-deleted");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store,
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = LocalFilePurger::new(scheduler.clone(), layer, None);
+
+        // Add an index reference
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+        file_purger.add_index_reference(index_id);
+
+        // Mark as deleted
+        let should_delete = file_purger.mark_index_deleted(&index_id);
+        assert!(!should_delete); // Should not delete as ref_count is 1
+
+        // Remove the reference
+        let should_delete = file_purger.remove_index_reference(&index_id);
+        assert!(should_delete); // Should delete as is_deleted is true and ref_count is 0
+
+        // Index should be removed from map
+        assert!(file_purger.index_refs.get(&index_id).is_none());
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    // Tests for Deletion Logic
+
+    #[tokio::test]
+    async fn test_mark_index_deleted() {
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-mark-index-deleted");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store,
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = LocalFilePurger::new(scheduler.clone(), layer, None);
+
+        // Test marking a non-existent index as deleted
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+        let should_delete = file_purger.mark_index_deleted(&index_id);
+        assert!(should_delete); // Should delete immediately as no references exist
+
+        // Test marking an existing index as deleted
+        file_purger.add_index_reference(index_id);
+        let should_delete = file_purger.mark_index_deleted(&index_id);
+        assert!(!should_delete); // Should not delete as ref_count is 1
+
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert!(info.is_deleted);
+            assert_eq!(info.ref_count, 1);
+        } // info is dropped here
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn test_check_and_delete_index() {
+        common_telemetry::init_default_ut_logging();
+
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-check-delete-index");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store.clone(),
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = LocalFilePurger::new(scheduler.clone(), layer, None);
+
+        // Create an index file
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+        let index_path = location::index_file_path("table1", index_id, PathType::Bare);
+        object_store
+            .write(&index_path, vec![0; 4096])
+            .await
+            .unwrap();
+
+        // Create a file meta with the index
+        let file_meta = FileMeta {
+            region_id: file_id.region_id(),
+            file_id: file_id.file_id(),
+            time_range: FileTimeRange::default(),
+            level: 0,
+            file_size: 4096,
+            available_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            indexes: vec![ColumnIndexMetadata {
+                column_id: 0,
+                created_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            }],
+            index_file_size: 4096,
+            index_version: 1,
+            num_rows: 1024,
+            num_row_groups: 1,
+            sequence: NonZeroU64::new(4096),
+            partition_expr: None,
+            num_series: 0,
+        };
+
+        // Add reference and check that index is not deleted
+        file_purger.add_index_reference(index_id);
+        file_purger.check_and_delete_index(file_meta.clone(), 1);
+
+        // Index should still exist
+        assert!(object_store.exists(&index_path).await.unwrap());
+
+        // Remove reference and mark as deleted
+        file_purger.remove_index_reference(&index_id);
+        file_purger.check_and_delete_index(file_meta, 1);
+
+        // Wait for async deletion
+        tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
+
+        // Index should be deleted
+        assert!(!object_store.exists(&index_path).await.unwrap());
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    // Tests for FileHandle Lifecycle Integration
+
+    #[tokio::test]
+    async fn test_file_handle_lifecycle_with_index() {
+        common_telemetry::init_default_ut_logging();
+
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-file-handle-lifecycle");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store.clone(),
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = Arc::new(LocalFilePurger::new(scheduler.clone(), layer.clone(), None));
+
+        // Create a file with index
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+        let file_path = location::sst_file_path("table1", file_id, PathType::Bare);
+        let index_path = location::index_file_path("table1", index_id, PathType::Bare);
+
+        object_store.write(&file_path, vec![0; 4096]).await.unwrap();
+        object_store
+            .write(&index_path, vec![0; 4096])
+            .await
+            .unwrap();
+
+        let file_meta = FileMeta {
+            region_id: file_id.region_id(),
+            file_id: file_id.file_id(),
+            time_range: FileTimeRange::default(),
+            level: 0,
+            file_size: 4096,
+            available_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            indexes: vec![ColumnIndexMetadata {
+                column_id: 0,
+                created_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            }],
+            index_file_size: 4096,
+            index_version: 1,
+            num_rows: 1024,
+            num_row_groups: 1,
+            sequence: NonZeroU64::new(4096),
+            partition_expr: None,
+            num_series: 0,
+        };
+
+        // Create FileHandle - this should add a reference
+        let handle = FileHandle::new(file_meta.clone(), file_purger.clone());
+
+        // Check that reference was added
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 1);
+            assert!(!info.is_deleted);
+        } // info is dropped here
+
+        // Clone the handle to increase reference count
+        let handle2 = handle.clone();
+
+        // Check that reference count is still 1 (only one FileHandleInner)
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 1);
+        } // info is dropped here
+
+        // Mark file as deleted
+        handle.mark_deleted();
+
+        // Drop one handle - should not delete yet
+        drop(handle);
+
+        // File and index should still exist
+        assert!(object_store.exists(&file_path).await.unwrap());
+        assert!(object_store.exists(&index_path).await.unwrap());
+
+        // Drop the second handle - should delete now
+        drop(handle2);
+
+        // Wait for async deletion
+        tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
+
+        // File and index should be deleted
+        assert!(!object_store.exists(&file_path).await.unwrap());
+        assert!(!object_store.exists(&index_path).await.unwrap());
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn test_update_index_version() {
+        common_telemetry::init_default_ut_logging();
+
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-update-index-version");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store.clone(),
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = Arc::new(LocalFilePurger::new(scheduler.clone(), layer.clone(), None));
+
+        // Create a file with index version 1
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let old_index_id = RegionIndexId::new(file_id, 1);
+        let new_index_id = RegionIndexId::new(file_id, 2);
+        let old_index_path = location::index_file_path("table1", old_index_id, PathType::Bare);
+        let new_index_path = location::index_file_path("table1", new_index_id, PathType::Bare);
+
+        object_store
+            .write(&old_index_path, vec![0; 4096])
+            .await
+            .unwrap();
+        object_store
+            .write(&new_index_path, vec![0; 4096])
+            .await
+            .unwrap();
+
+        let file_meta = FileMeta {
+            region_id: file_id.region_id(),
+            file_id: file_id.file_id(),
+            time_range: FileTimeRange::default(),
+            level: 0,
+            file_size: 4096,
+            available_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            indexes: vec![ColumnIndexMetadata {
+                column_id: 0,
+                created_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            }],
+            index_file_size: 4096,
+            index_version: 2, // New version
+            num_rows: 1024,
+            num_row_groups: 1,
+            sequence: NonZeroU64::new(4096),
+            partition_expr: None,
+            num_series: 0,
+        };
+
+        // Create FileHandle with new index version - this should add reference to new index
+        let handle = FileHandle::new(file_meta.clone(), file_purger.clone());
+
+        // Check that reference was added to new index
+        {
+            let info = file_purger.index_refs.get(&new_index_id).unwrap();
+            assert_eq!(info.ref_count, 1);
+            assert!(!info.is_deleted);
+        } // info is dropped here
+
+        // Update index - this should mark old index as deleted
+        file_purger.update_index(file_meta.clone(), 1);
+
+        // Check that old index is marked as deleted
+        {
+            let info = file_purger.index_refs.get(&old_index_id);
+            // Old index should not exist as it had no references
+            assert!(info.is_none());
+        } // info is dropped here
+
+        // New index should still have its reference
+        {
+            let info = file_purger.index_refs.get(&new_index_id).unwrap();
+            assert_eq!(info.ref_count, 1);
+            assert!(!info.is_deleted);
+        } // info is dropped here
+
+        // Drop the handle
+        drop(handle);
+
+        // Wait for async operations
+        tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
+
+        // New index should still exist as it was the current one
+        assert!(object_store.exists(&new_index_path).await.unwrap());
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    // Tests for Edge Cases and Error Conditions
+
+    #[tokio::test]
+    async fn test_concurrent_index_operations() {
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-concurrent-index-ops");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store,
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = Arc::new(LocalFilePurger::new(scheduler, layer, None));
+
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+
+        let mut handles = vec![];
+
+        // Spawn multiple threads to add references concurrently
+        for _ in 0..10 {
+            let purger = file_purger.clone();
+            let idx = index_id;
+            let handle = tokio::spawn(async move {
+                purger.add_index_reference(idx);
+            });
+            handles.push(handle);
+        }
+
+        // Wait for all operations to complete
+        for handle in handles {
+            handle.await.unwrap();
+        }
+
+        // Check that all 10 references were added
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 10);
+            assert!(!info.is_deleted);
+        } // info is dropped here
+
+        // Spawn multiple threads to remove references concurrently
+        let mut handles = vec![];
+        for _ in 0..10 {
+            let purger = file_purger.clone();
+            let idx = index_id;
+            let handle = tokio::spawn(async move {
+                purger.remove_index_reference(&idx);
+            });
+            handles.push(handle);
+        }
+
+        // Wait for all operations to complete
+        for handle in handles {
+            handle.await.unwrap();
+        }
+
+        // Index should be removed as ref_count is 0
+        assert!(file_purger.index_refs.get(&index_id).is_none());
+    }
+
+    #[tokio::test]
+    async fn test_multiple_file_handles_same_index() {
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-multiple-handles-same-index");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store,
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = Arc::new(LocalFilePurger::new(scheduler, layer, None));
+
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+
+        let file_meta = FileMeta {
+            region_id: file_id.region_id(),
+            file_id: file_id.file_id(),
+            time_range: FileTimeRange::default(),
+            level: 0,
+            file_size: 4096,
+            available_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            indexes: vec![ColumnIndexMetadata {
+                column_id: 0,
+                created_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            }],
+            index_file_size: 4096,
+            index_version: 1,
+            num_rows: 1024,
+            num_row_groups: 1,
+            sequence: NonZeroU64::new(4096),
+            partition_expr: None,
+            num_series: 0,
+        };
+
+        // Create multiple FileHandles for the same file
+        let handle1 = FileHandle::new(file_meta.clone(), file_purger.clone());
+        let handle2 = FileHandle::new(file_meta.clone(), file_purger.clone());
+        let handle3 = FileHandle::new(file_meta, file_purger.clone());
+
+        // Each FileHandle should add a reference
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 3);
+        } // info is dropped here
+
+        // Mark all handles as deleted
+        handle1.mark_deleted();
+        handle2.mark_deleted();
+        handle3.mark_deleted();
+
+        // Drop one handle - should not delete yet
+        drop(handle1);
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 2);
+        } // info is dropped here
+
+        // Drop another handle - should not delete yet
+        drop(handle2);
+        {
+            let info = file_purger.index_refs.get(&index_id).unwrap();
+            assert_eq!(info.ref_count, 1);
+        } // info is dropped here
+
+        // Drop the last handle - should delete now
+        drop(handle3);
+
+        // Index should be removed from map
+        assert!(file_purger.index_refs.get(&index_id).is_none());
+    }
+
+    #[tokio::test]
+    async fn test_error_handling_during_deletion() {
+        common_telemetry::init_default_ut_logging();
+
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-error-handling-deletion");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store.clone(),
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = Arc::new(LocalFilePurger::new(scheduler.clone(), layer.clone(), None));
+
+        // Create a file with index
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+        let file_path = location::sst_file_path("table1", file_id, PathType::Bare);
+        let index_path = location::index_file_path("table1", index_id, PathType::Bare);
+
+        object_store.write(&file_path, vec![0; 4096]).await.unwrap();
+        object_store
+            .write(&index_path, vec![0; 4096])
+            .await
+            .unwrap();
+
+        let file_meta = FileMeta {
+            region_id: file_id.region_id(),
+            file_id: file_id.file_id(),
+            time_range: FileTimeRange::default(),
+            level: 0,
+            file_size: 4096,
+            available_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            indexes: vec![ColumnIndexMetadata {
+                column_id: 0,
+                created_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            }],
+            index_file_size: 4096,
+            index_version: 1,
+            num_rows: 1024,
+            num_row_groups: 1,
+            sequence: NonZeroU64::new(4096),
+            partition_expr: None,
+            num_series: 0,
+        };
+
+        // Create FileHandle
+        let handle = FileHandle::new(file_meta, file_purger.clone());
+
+        // Manually delete the index file to simulate an error during deletion
+        object_store.delete(&index_path).await.unwrap();
+
+        // Mark file as deleted and drop handle
+        handle.mark_deleted();
+        drop(handle);
+
+        // Wait for async deletion - should handle error gracefully
+        tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
+
+        // File should still be deleted despite index deletion error
+        assert!(!object_store.exists(&file_path).await.unwrap());
+
+        scheduler.stop(true).await.unwrap();
+    }
+
+    // Tests for Integration with Storage Layer
+
+    #[tokio::test]
+    async fn test_local_file_system_integration() {
+        common_telemetry::init_default_ut_logging();
+
+        let scheduler = Arc::new(LocalScheduler::new(3));
+        let dir = create_temp_dir("test-local-fs-integration");
+        let dir_path = dir.path().display().to_string();
+        let builder = Fs::default().root(&dir_path);
+        let object_store = ObjectStore::new(builder).unwrap().finish();
+
+        let index_aux_path = dir.path().join("index_aux");
+        let puffin_mgr = PuffinManagerFactory::new(&index_aux_path, 4096, None, None)
+            .await
+            .unwrap();
+        let intm_mgr = IntermediateManager::init_fs(index_aux_path.to_str().unwrap())
+            .await
+            .unwrap();
+
+        let layer = Arc::new(AccessLayer::new(
+            "table1",
+            PathType::Bare,
+            object_store.clone(),
+            puffin_mgr,
+            intm_mgr,
+        ));
+
+        let file_purger = Arc::new(LocalFilePurger::new(scheduler.clone(), layer.clone(), None));
+
+        // Create a file with index
+        let file_id = RegionFileId::new(RegionId::new(0, 0), FileId::random());
+        let index_id = RegionIndexId::new(file_id, 1);
+        let file_path = location::sst_file_path("table1", file_id, PathType::Bare);
+        let index_path = location::index_file_path("table1", index_id, PathType::Bare);
+
+        object_store.write(&file_path, vec![0; 4096]).await.unwrap();
+        object_store
+            .write(&index_path, vec![0; 4096])
+            .await
+            .unwrap();
+
+        let file_meta = FileMeta {
+            region_id: file_id.region_id(),
+            file_id: file_id.file_id(),
+            time_range: FileTimeRange::default(),
+            level: 0,
+            file_size: 4096,
+            available_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            indexes: vec![ColumnIndexMetadata {
+                column_id: 0,
+                created_indexes: SmallVec::from_iter([IndexType::InvertedIndex]),
+            }],
+            index_file_size: 4096,
+            index_version: 1,
+            num_rows: 1024,
+            num_row_groups: 1,
+            sequence: NonZeroU64::new(4096),
+            partition_expr: None,
+            num_series: 0,
+        };
+
+        // Create FileHandle
+        let handle = FileHandle::new(file_meta, file_purger.clone());
+
+        // Verify files exist
+        assert!(object_store.exists(&file_path).await.unwrap());
+        assert!(object_store.exists(&index_path).await.unwrap());
+
+        // Mark file as deleted and drop handle
+        handle.mark_deleted();
+        drop(handle);
+
+        // Wait for async deletion
+        tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
+
+        // Verify files are deleted
+        assert!(!object_store.exists(&file_path).await.unwrap());
+        assert!(!object_store.exists(&index_path).await.unwrap());
+
+        scheduler.stop(true).await.unwrap();
+    }
 }