recovery_min_apply_delay

recovery_min_apply_delay sets the minimum delay for applying changes during recovery. It is a sighup setting present in PG12–18; the latest recorded boot default is 0 ms.

Note

Fact — official short description: “Sets the minimum delay for applying changes during recovery.”

Identity

Type , Valueinteger: Upstream pg_settings type
Context , Valuesighup: Takes effect after configuration reload
Unit , Valuems: Raw unit
Range , Value0 – 2147483647: Raw limits in the last observed version
Enum values , Value—: — for non-enum types
Category , ValueReplication / Standby Servers: Upstream classification
Latest boot value , Value0: 0 ms

Lifecycle

Fact	Value
First observed	PG12
Present in	PG12–19 Beta 3
Removed in	No
Introduction commit	`2dedf4d9a899` — Integrate recovery.conf into postgresql.conf
Commit date	2018-11-25
Discussion	thread 1

Default history

Measured PG9.0–19 Beta 3 boot defaults
Versions	Raw `boot_val`	Unit	Human value
PG12–19 Beta 3	`0`	`ms`	0 ms

How it works

Sets the minimum delay for applying changes during recovery. A configuration reload applies a new value; existing work already in flight is not retroactively changed.

A standby delays replay of each transaction commit until the configured time has elapsed since the primary’s commit timestamp. Network/cascade lag counts toward the delay, clocks matter, and synchronous_commit=remote_apply makes primary commits wait through the intentional delay.

Monitor and change recovery_min_apply_delay together with max_standby_archive_delay, max_standby_streaming_delay, hot_standby. Validate on the relevant server role and real workload, then use its sighup context to choose session change, reload, or restart; a historical boot default is not the current effective value.

Tuning advice

Tip

Advice. These are workload-specific starting points and must be validated with measurements.

Workload	Guidance
OLTP	Size recovery_min_apply_delay from topology, failover roles, slot/subscription count, and reconnect headroom. Test worst-case primary latency, standby replay, and disk retention before production.
OLAP	Read standbys and logical subscribers often see long queries or large transactions. Put explicit bounds on replay/apply and monitor lag, worker saturation, slot restart_lsn, and conflict cancellations.
Small nodes	Configure only replication capacity that is actually used. Even a small topology needs bounded timeouts and slot lifecycle; unlimited retention is not reliability.

Pigsty

Values use the fixed 8-vCPU, 32-GiB, 100-GiB SSD fixture and render the current Pigsty templates for PG19 Beta 3; this does not assert current Pigsty support for that historical or beta release.

Template	Effective value	Versus upstream boot	Source expression
OLTP	Unmodified	—	—
OLAP	Unmodified	—	—
CRIT	Unmodified	—	—
TINY	Unmodified	—	—

Caution

Advice — pending human review. Fact from the current Pigsty template projection: OLTP: PG12–19 Beta 3 unmodified; OLAP: PG12–19 Beta 3 unmodified; CRIT: PG12–19 Beta 3 unmodified; TINY: PG12–19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.

Common pitfalls

Changing it on the wrong primary, standby, sender, or subscriber role.
Watching only configured bytes/time instead of actual lag, slot position, and worker state.
Failing over to a node that lacks the old primary’s capacity or prerequisites.
Using infinite waits or WAL retention to hide a failed consumer.

max_standby_archive_delay · max_standby_streaming_delay · hot_standby · hot_standby_feedback · primary_conninfo · primary_slot_name