sharedbuffers: knowledge that doesn't get lost on disk

Tue, 21 Apr 2026 00:00:00 +0000

In PostgreSQL, shared_buffers is the parameter that defines the size of the buffer pool — the memory area where data pages are kept warm so queries don’t need to hit the disk on every access.

When a page is in the buffer, it’s immediately available to any database process. That’s the point: shared memory that speeds everything up.

This blog’s name comes from that, but the metaphor goes a bit further than the parameter.

Introduction on sharedbuffers

sharedbuffers: knowledge that doesn't get lost on disk