Specifies the maximum number of replication slots for use of the REPACK command.
At a glance
| Property | Value |
|---|---|
| Parameter | max_repack_replication_slots |
| Category | Replication |
| Default | 5 |
| Value type | integer |
| Change scope | Server restart required (postgresql.conf) |
| Available in | PostgreSQL 19 (added in 19) |
What it does
Specifies the maximum number of replication slots for use of the REPACK command. The default is 5. This parameter can only be set at server start.
(Description quoted from the official PostgreSQL documentation.)
How to apply a change
Set it in postgresql.conf (or with ALTER SYSTEM) and restart the server — this parameter cannot change without a restart.
Inspect the current value and source with SHOW max_repack_replication_slots; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'max_repack_replication_slots';.
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.