From e64469bbc444aea0a6240efc8c76ad1406a8944b Mon Sep 17 00:00:00 2001
From: discord9 <55937128+discord9@users.noreply.github.com>
Date: Tue, 5 Aug 2025 19:45:47 +0800
Subject: [PATCH] fix: not mark all deleted when partial trunc (#6654)

* fix: not mark all deleted when partial trunc&not update manifest when partial file range is empty

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

* docs: note

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

---------

Signed-off-by: discord9 <discord9@163.com>
---
 src/mito2/src/region/version.rs         | 42 +++++++++++++++----------
 src/mito2/src/worker/handle_truncate.rs | 24 +++++++++-----
 2 files changed, 42 insertions(+), 24 deletions(-)

diff --git a/src/mito2/src/region/version.rs b/src/mito2/src/region/version.rs
index 5c740c3071..bf425f9f7f 100644
--- a/src/mito2/src/region/version.rs
+++ b/src/mito2/src/region/version.rs
@@ -209,27 +209,35 @@ impl VersionControl {
             next_memtable_id,
             Some(part_duration),
         ));
-        let new_version = match truncate_kind {
+        match truncate_kind {
             TruncateKind::All {
                 truncated_entry_id,
                 truncated_sequence,
-            } => Arc::new(
-                VersionBuilder::new(version.metadata.clone(), new_mutable)
-                    .flushed_entry_id(truncated_entry_id)
-                    .flushed_sequence(truncated_sequence)
-                    .truncated_entry_id(Some(truncated_entry_id))
-                    .build(),
-            ),
-            TruncateKind::Partial { files_to_remove } => Arc::new(
-                VersionBuilder::from_version(version)
-                    .remove_files(files_to_remove.into_iter())
-                    .build(),
-            ),
-        };
+            } => {
+                let new_version = Arc::new(
+                    VersionBuilder::new(version.metadata.clone(), new_mutable)
+                        .flushed_entry_id(truncated_entry_id)
+                        .flushed_sequence(truncated_sequence)
+                        .truncated_entry_id(Some(truncated_entry_id))
+                        .build(),
+                );
 
-        let mut version_data = self.data.write().unwrap();
-        version_data.version.ssts.mark_all_deleted();
-        version_data.version = new_version;
+                let mut version_data = self.data.write().unwrap();
+                version_data.version.ssts.mark_all_deleted();
+                version_data.version = new_version;
+            }
+            TruncateKind::Partial { files_to_remove } => {
+                let new_version = Arc::new(
+                    VersionBuilder::from_version(version)
+                        .remove_files(files_to_remove.into_iter())
+                        .build(),
+                );
+
+                let mut version_data = self.data.write().unwrap();
+                // notice since it's partial, no need to mark all files as deleted
+                version_data.version = new_version;
+            }
+        };
     }
 
     /// Overwrites the current version with a new version.
diff --git a/src/mito2/src/worker/handle_truncate.rs b/src/mito2/src/worker/handle_truncate.rs
index d571b99abe..13e7fa2520 100644
--- a/src/mito2/src/worker/handle_truncate.rs
+++ b/src/mito2/src/worker/handle_truncate.rs
@@ -37,7 +37,7 @@ impl<S: LogStore> RegionWorkerLoop<S> {
         };
         let version_data = region.version_control.current();
 
-        let truncate = match req {
+        match req {
             RegionTruncateRequest::All => {
                 info!("Try to fully truncate region {}", region_id);
 
@@ -45,13 +45,15 @@ impl<S: LogStore> RegionWorkerLoop<S> {
                 let truncated_sequence = version_data.committed_sequence;
 
                 // Write region truncated to manifest.
-                RegionTruncate {
+                let truncate = RegionTruncate {
                     region_id,
                     kind: TruncateKind::All {
                         truncated_entry_id,
                         truncated_sequence,
                     },
-                }
+                };
+
+                self.handle_manifest_truncate_action(region, truncate, sender);
             }
             RegionTruncateRequest::ByTimeRanges { time_ranges } => {
                 info!(
@@ -79,16 +81,24 @@ impl<S: LogStore> RegionWorkerLoop<S> {
                     files_to_truncate.len(),
                     region_id
                 );
-                RegionTruncate {
+
+                // this could happen if all files are not fully contained in the time ranges
+                if files_to_truncate.is_empty() {
+                    info!("No files to truncate in region {}", region_id);
+                    // directly send success back as no files to truncate
+                    // and no background notify is needed
+                    sender.send(Ok(0));
+                    return;
+                }
+                let truncate = RegionTruncate {
                     region_id,
                     kind: TruncateKind::Partial {
                         files_to_remove: files_to_truncate,
                     },
-                }
+                };
+                self.handle_manifest_truncate_action(region, truncate, sender);
             }
         };
-
-        self.handle_manifest_truncate_action(region, truncate, sender);
     }
 
     /// Handles truncate result.