OceanBase v4.4.1_CE_HF2: Stabilizing Vector Search and Resolving Memory Leaks

OceanBase has rolled out version 4.4.1_CE_HF2, addressing several critical stability issues, particularly within its vector search capabilities. Released on December 24, 2025, this release targets memory management, query latency, and data integrity.

Version Details

  • Release Date: December 24, 2025
  • Version: V4.4.1_CE_HF2
  • Commit: 2fb6704
  • RPM: oceanbase-ce-4.4.1.0-100020022025121814

Vector Search Improvements

This release focuses heavily on stabilizing vector operations, which are prone to performance degradation and crashes under specific workloads.

  • Memory Management: The team fixed high memory usage in the ModulePageAlloc module on vector follower nodes. They also addressed core dumps triggered by memory allocation failures during the data repair process.
  • Latency and Locking: A tenant-level lock issue causing Real-Time (RT) spikes in vector queries has been resolved.
  • Index Management: The release corrects disk space bloat that occurred when dropping or rebuilding vector indexes. It also fixes core dumps caused by multi-value index arrays exceeding 32 elements.

Query Accuracy and Hybrid Search

The update improves the reliability of hybrid search (混搜) in complex scenarios.

  • JOIN and GROUP BY: Accuracy issues in heap partitioned tables have been fixed for hybrid search operations involving joins and group by clauses.
  • Parameter Limits: The ef_search parameter limit has been raised to topK * 10, allowing for more flexible search configurations.
  • SQL Parsing: The interface now correctly handles special characters when converting SQL for hybrid search.

System Stability

  • OBKV Locks: Correctness issues in retry logic for OBKV row lock conflicts have been addressed.
  • External Tables: The system now handles scenarios with a high number of external table files without throwing errors.