Maximum concurrent autovacuum worker processes.
At a glance
| Property | Value |
|---|---|
| Parameter | autovacuum_max_workers |
| Category | Autovacuum |
| Default | 3 |
| Value type | boolean / enum / numeric |
| Change scope | Restart required |
What it does
Maximum number of autovacuum workers that may run at once across the cluster.
How to apply a change
Requires a full server restart (postmaster context). Set it in postgresql.conf and restart PostgreSQL.
Inspect the current value and source with SHOW autovacuum_max_workers; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'autovacuum_max_workers';.
Tuning guidance
Raise to 4-6 on databases with many large, churned tables so big tables do not starve small ones. Remember the cost-limit budget is shared across all workers.