Specifies the scaling factor of the transaction ID age component of the score used by autovacuum for prioritization purposes.
At a glance
| Property | Value |
|---|---|
| Parameter | autovacuum_freeze_score_weight |
| Category | Vacuuming |
| Default | 1.0 |
| Value type | floating point |
| Change scope | Reload (postgresql.conf, SIGHUP) |
| Available in | PostgreSQL 19 (added in 19) |
What it does
Specifies the scaling factor of the transaction ID age component of the score used by autovacuum for prioritization purposes. The default is 1.0. This parameter can only be set in the postgresql.conf file or on the server command line. See autovacuum_priority for more information.
(Description quoted from the official PostgreSQL documentation.)
How to apply a change
Set it in postgresql.conf (or with ALTER SYSTEM) and reload with SELECT pg_reload_conf(); or pg_ctl reload — no restart needed.
Inspect the current value and source with SHOW autovacuum_freeze_score_weight; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'autovacuum_freeze_score_weight';.
Tuning guidance
This parameter is rarely a performance lever. Leave it at the default unless you have a specific, documented reason to change it, change it on one session or one role/database first, and confirm the effect with pg_settings and your own measurements before rolling it out cluster-wide.