log_rotation_age

log_rotation_age is the PostgreSQL setting that defines the amount of time to wait before forcing log file rotation.

Note

Fact — official short description: “Sets the amount of time to wait before forcing log file rotation.”

Identity

Type , Valueinteger: Upstream pg_settings type
Context , Valuesighup: Takes effect after configuration reload
Unit , Valuemin: Raw unit
Range , Value0 – 35791394: Raw limits in the last observed version
Enum values , Value—: — for non-enum types
Category , ValueReporting and Logging / Where to Log: Upstream classification
Latest boot value , Value1440: 1 d

Lifecycle

Fact	Value
First observed	PG9.0 (research boundary)
Present in	PG9.0–19 Beta 3
Removed in	No
Introduction commit	Not asserted: predates the PG9.0 research boundary
Commit date	—
Discussion	—

Default history

Measured PG9.0–19 Beta 3 boot defaults
Versions	Raw `boot_val`	Unit	Human value
PG9.0–19 Beta 3	`1440`	`min`	1 d

How it works

log_rotation_age sets the amount of time to wait before forcing log file rotation. 0 disables time-based creation of new log files. The collector opens a new file after the interval; zero disables this trigger but leaves size-based or external rotation possible.

log_rotation_age is a SIGHUP-context setting: a configuration reload activates the new server value without a restart; subsequent operations that consult it use the refreshed value.

The active path is composed from log_destination, logging_collector or syslog/eventlog, file naming and permissions, rotation triggers, and external shipping or retention.

Tuning advice

Tip

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

Workload	Guidance
OLTP	Set log_rotation_age from the maximum time a file may remain open and the shipping/retention boundary. Confirm that the filename pattern creates a distinct or intentionally reusable name at that interval.
OLAP	Long analytical bursts do not require a different clock by themselves; choose an interval that lets downstream systems close and ingest files predictably without producing impractically large objects.
Small nodes	Prefer a simple daily or shorter interval that keeps failure blast radius bounded. Zero disables time rotation and is safe only when size-based or external rotation is authoritative and tested.

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	`1d`	same as boot	`'1d'`
OLAP	`1d`	same as boot	`'1d'`
CRIT	`1d`	same as boot	`'1d'`
TINY	`1d`	same as boot	`'1d'`

Caution

Advice — pending human review. Fact from the current Pigsty template projection: OLTP: PG9.0–19 Beta 3 = 1d (dcs); OLAP: PG9.0–19 Beta 3 = 1d (dcs); CRIT: PG9.0–19 Beta 3 = 1d (dcs); TINY: PG9.0–19 Beta 3 = 1d (dcs). Advice, pending human review — Editorial inference: Daily rotation matches the weekday filename cycle and creates predictable operational boundaries.

Common pitfalls

Editing log_rotation_age without reloading configuration and verifying the effective value and subsequent behavior.
Combining incompatible destination, collector, filename, and rotation assumptions and then losing or overwriting logs.
Failing to monitor a full or unwritable log target, which can block logging or database activity depending on the path.
Changing log_rotation_age globally without a rollback plan and a client or operational compatibility test.

logging_collector · log_destination · log_directory · log_filename · log_rotation_size