recovery_init_sync_method

recovery_init_sync_method sets the method for synchronizing the data directory before crash recovery. It is a sighup setting present in PG14–18; the latest recorded boot default is fsync.

Note

Fact — official short description: “Sets the method for synchronizing the data directory before crash recovery.”

Identity

Type , Valueenum: Upstream pg_settings type
Context , Valuesighup: Takes effect after configuration reload
Unit , Value—: Raw unit
Range , Value—: Raw limits in the last observed version
Enum values , Valuefsync, syncfs: — for non-enum types
Category , ValueError Handling: Upstream classification
Latest boot value , Valuefsync: fsync

Lifecycle

Fact	Value
First observed	PG14
Present in	PG14–19 Beta 3
Removed in	No
Introduction commit	`61752afb2640` — Provide recovery_init_sync_method=syncfs.
Commit date	2021-03-20
Discussion	thread 1 · thread 2

Default history

Measured PG9.0–19 Beta 3 boot defaults
Versions	Raw `boot_val`	Unit	Human value
PG14–19 Beta 3	`fsync`	—	fsync

How it works

Sets the method for synchronizing the data directory before crash recovery. A configuration reload applies a new value; existing work already in flight is not retroactively changed.

Before crash recovery, PostgreSQL synchronizes the data directory so replay is not built on unflushed copied files. fsync walks files portably; where supported, syncfs can synchronize the containing filesystem more quickly but has a broader scope.

Monitor and change recovery_init_sync_method together with data_sync_retry, restart_after_crash, fsync. 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	Change recovery_init_sync_method only from an explicit failure model and measured evidence. Validate in a session/test environment, deploy according to its context, and retain a rollback value.
OLAP	Test separately under long queries, batch jobs, and peak concurrency rather than copying OLTP assumptions to analytical nodes.
Small nodes	Keep the default without a concrete problem; small systems should not trade global compatibility or failure semantics for a marginal gain.

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: PG14–19 Beta 3 unmodified; OLAP: PG14–19 Beta 3 unmodified; CRIT: PG14–19 Beta 3 unmodified; TINY: PG14–19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.

Common pitfalls

Confusing the boot default of recovery_init_sync_method with its current effective value.
Ignoring its sighup context when deciding when it takes effect.
Changing several interacting settings at once and losing causal evidence.
Rolling out globally without testing the real failure or workload boundary.

data_sync_retry · restart_after_crash · fsync · full_page_writes · exit_on_error