Parameter · Vacuuming / Automatic Vacuuming

autovacuum_analyze_threshold

Minimum number of tuple inserts, updates, or deletes prior to analyze.

Default: 50
Type: integer
Range: 0 … 2147483647
Applies: Reload

In plain words

The planner relies on statistics about each table. Autovacuum re-runs ANALYZE when threshold + 10% of the rows have been inserted, updated or deleted since the last analyze. This is the fixed part.

For DBAs and operators

anl_thresh = autovacuum_analyze_threshold + autovacuum_analyze_scale_factor * reltuples
analyze if n_mod_since_analyze > anl_thresh

Unlike vacuum, there is no max cap. Gotchas:

Partitioned tables (the parent) are never analyzed by autovacuum; only their leaf partitions are. Run ANALYZE parent yourself (e.g. after big loads) or queries on the parent get poor estimates.
Temporary tables are not seen by autovacuum at all.
After pg_upgrade statistics are kept since PostgreSQL 18, but extended statistics still need ANALYZE; after a crash the counters reset.

ALTER TABLE orders SET (autovacuum_analyze_threshold = 10000,
                        autovacuum_analyze_scale_factor = 0);

How to change it

Change in postgresql.conf or ALTER SYSTEM, then run SELECT pg_reload_conf().

See it in context

ANALYZE and statistics Autovacuum: when tables get vacuumed

Related parameters

autovacuum_analyze_scale_factor autovacuum_vacuum_threshold default_statistics_target

All Vacuuming parameters