Two EXPLAIN ANALYZE runs on statistically identical data produced opposite plans, 73 heap blocks against 3,449. The margin was 1.5%. Here's the mechanism, measured with ExoBench, and the index shape that takes the coin out of the planner's…
The `notify_buffers` GUC tunes a 128kB cache for PostgreSQL's LISTEN/NOTIFY queue—and almost never matters. (I consult on PostgreSQL through PGX Inc..)
PostgreSQL connection poolers lie to both sides of the wire: your app thinks it has thousands of connections while the database sees dozens. (I consult on PostgreSQL through PGX Inc..)
pgvector 0.8.7 fixes CVE-2026-103484: a database user who can create an IVFFlat index can write out of bounds in the backend, which can lead to arbitrary code execution. Every version through 0.8.6 is affected. Upgrade. That part is…