From a7cdfd27d56d8b1be510e6299641ec23e95e79eb Mon Sep 17 00:00:00 2001
From: Andrey Vasnetsov <andrey@vasnetsov.com>
Date: Sun, 11 Jan 2026 23:58:45 +0100
Subject: [PATCH] log mutable id tracker mapping updates (#7894)

* add log for persisting id-tracker changes

* trace log flush topology

* fmt

* make trace
---
 lib/segment/src/id_tracker/mutable_id_tracker.rs | 2 ++
 lib/shard/src/segment_holder/flush.rs            | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/lib/segment/src/id_tracker/mutable_id_tracker.rs b/lib/segment/src/id_tracker/mutable_id_tracker.rs
index 7d2f43e677..db83550569 100644
--- a/lib/segment/src/id_tracker/mutable_id_tracker.rs
+++ b/lib/segment/src/id_tracker/mutable_id_tracker.rs
@@ -468,6 +468,8 @@ fn store_mapping_changes(
 
     let mut writer = BufWriter::new(file);
 
+    log::trace!("writing mapping changes to {mappings_path:?}: {changes:?}");
+
     write_mapping_changes(&mut writer, changes).map_err(|err| {
         OperationError::service_error(format!(
             "Failed to persist ID tracker point mappings ({}): {err}",
diff --git a/lib/shard/src/segment_holder/flush.rs b/lib/shard/src/segment_holder/flush.rs
index 75803c4a25..5a5105ae02 100644
--- a/lib/shard/src/segment_holder/flush.rs
+++ b/lib/shard/src/segment_holder/flush.rs
@@ -3,6 +3,7 @@ use std::sync::atomic::Ordering;
 use std::thread::JoinHandle;
 
 use common::sort_utils::sort_permutation;
+use log::trace;
 use parking_lot::{RwLock, RwLockReadGuard};
 use segment::common::operation_error::{OperationError, OperationResult};
 use segment::entry::SegmentEntry;
@@ -121,6 +122,8 @@ impl SegmentHolder {
 
     fn sort_segment_ids_by_flush_dependency(&self, segment_ids: &[SegmentId]) -> Vec<SegmentId> {
         let flush_topology = self.flush_dependency.lock().clone();
+        trace!("{flush_topology:?}");
+
         let mut iter = flush_topology.sort_elements(segment_ids);
         let sorted_keys: Vec<_> = iter.by_ref().collect();