In Ceph version 17.2.5, a notable performance drop is observed when executing list operations on non-existent objects, especially for large buckets undergoing high concurrency with frequent updates. For the context, initiating concurrent PUT/DELETE/LIST operations on 4 buckets, each containing ~10 million objects, initially yields satisfactory latencies. However, as updates continue to accumulate, the efficiency of the `negative list` operation diminishes notably. I suspect that over time, with many object insertions and deletions, the bucket index gets fragmented. While this affects all operations, negative lookups appear to be particularly hampered, possibly because they necessitate a comprehensive scan of the fragmented index. With the LIST arguments defined as $prefix=xxx $max-keys=2, are there any recommendations to optimize the Ceph configuration to enhance the performance of negative list operations?