9 min read
TOAST quietly moves your large values off-page and compresses them. It's invisible until a query that only touches small columns suddenly drags, and the cause is a wide column you forgot was there.
PostgreSQL Topic Archive
Vacuum and Bloat PostgreSQL Articles
Autovacuum, dead tuples, bloat, wraparound, MVCC, freeze age, and visibility.
9 min read
A table with one million live rows was holding five million dead ones, and queries were scanning all six. Understanding xmin, xmax, and how PostgreSQL decides what a query can see explains where the dead rows come from.
11 min read
Autovacuum is not just cleanup. When it falls behind, dead tuples, bloated indexes, stale statistics, and transaction age turn into slow queries and operational risk.
13 min read
VACUUM problems are cleanup debt. Dead tuples, bloat, frozen XIDs, and autovacuum lag turn normal queries into incident material when nobody is watching.
6 min read
Transaction ID wraparound is rare, dramatic, and entirely avoidable. Here is what FREEZE actually does, and the autovacuum settings that keep you out of single-user mode.
6 min read
Bloat measurement is useful only when it changes a cleanup decision. Learn when estimates are good enough, when pgstattuple is worth the cost, and what action follows.
6 min read
Wraparound emergencies are preventable, but once warnings start you need a calm runbook: identify old XIDs, unblock vacuum, freeze priority tables, and protect availability.