MatrixOne Files

Release date: September 17, 2026
MatrixOne version: v4.2.4

MatrixOne 4.2.4 is a patch release on top of 4.2.3, improving filtered vector search, multi-CN IVF result ordering, lock-service recovery, and memory reclamation under Linux VMA pressure.

Key Improvements

Vector Search

• Subquery Membership Filtering: Allow eligible IN-subquery SEMI JOIN queries to use the IVF pre-filter path, enforcing exact membership before candidate limiting. Unsupported query shapes retain the original relational plan.

Key Bug Fixes

Query Correctness

• Multi-CN IVF Ranking: Rank merged IVF candidates by distance before applying the global limit, preventing CN arrival order from discarding better candidates.

Reliability

• Stale Empty Locks: Recover stale empty row/range locks without the previous panic, while preserving range pairing and cleanup ownership.
• Memory Reclamation: Retain and retry mappings when Linux munmap returns ENOMEM under VMA pressure, with bounded recovery work and diagnostics. Fresh mmap admission pauses while reclamation remains pending.

What's Changed

• [4.2] fix(malloc): handle munmap ENOMEM with bounded recovery and diagnostics by @XuPeng-SH in https://github.com/matrixorigin/matrixone/pull/28739
• [4.2] fix(plan): use vector index with SEMI JOIN membership by @LeftHandCold in https://github.com/matrixorigin/matrixone/pull/28796
• fix(lockservice): backport stale empty-lock recovery to 4.2-dev by @VioletQwQ-0 in https://github.com/matrixorigin/matrixone/pull/28529
• fix: rank multi-CN IVF candidates before applying global limit by @iamlinjunhong in https://github.com/matrixorigin/matrixone/pull/29021

Full Changelog: https://github.com/matrixorigin/matrixone/compare/v4.2.3...v4.2.4