https://www.postgresscripts.com/tags/cache/Recent content in Cache on Postgres ScriptsHugo -- gohugo.ioenPostgresScripts.comThu, 14 May 2026 00:00:00 +0000https://www.postgresscripts.com/post/postgresql-table-cache-hit-ratio-pg-statio-user-tables/Thu, 14 May 2026 00:00:00 +0000https://www.postgresscripts.com/post/postgresql-table-cache-hit-ratio-pg-statio-user-tables/ <h2 id="measuring-postgresql-table-cache-efficiency-with-pg_statio_user_tables">Measuring PostgreSQL Table Cache Efficiency with pg_statio_user_tables</h2> <p>PostgreSQL keeps frequently accessed data pages in <code>shared_buffers</code> to avoid hitting disk. When a backend reads a data block, PostgreSQL first checks <code>shared_buffers</code>; if the block is there, it counts as a heap hit. If it is not, PostgreSQL reads from disk and counts it as a heap read. The ratio of hits to total reads — the table cache hit ratio — is a primary indicator of how well your <code>shared_buffers</code> setting matches your working data set.</p>