WAL & checkpointsRestart requireddefault replica

wal_level

Sets the level of information written to the WAL.

How you change it

Restart required

Defaults and ranges on this page were read from pg_settings on live PostgreSQL 18.4. Treat older majors as needing their own check before you copy a value.

What this means

Determines how much information is written to the WAL. 'replica' (the default) supports streaming replication and archiving; 'logical' adds the extra detail needed for logical replication and change-data-capture; 'minimal' writes the least but disallows WAL archiving and replication.

When it matters

Use 'replica' for physical standbys/PITR, 'logical' if you need logical replication or CDC.

Defaultreplica
Allowedminimal, replica, logical
Typeenum
Change scopeRestart required
CategoryWAL & checkpoints
Check the current value
SHOW wal_level;

Tradeoffs

  • 'minimal' blocks archiving and replicas, so it is only for isolated single-node setups.
  • 'logical' increases WAL volume; size archiving and disk accordingly.
  • Changing it requires a server restart.
PostgreSQL manual: wal_level

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