jit_provider

jit_provider is the PostgreSQL setting that selects the JIT provider.

Note

Fact — official short description: “JIT provider to use.”

Identity

Type , Valuestring: Upstream pg_settings type
Context , Valuepostmaster: Requires a server restart
Unit , Value—: Raw unit
Range , Value—: Raw limits in the last observed version
Enum values , Value—: — for non-enum types
Category , ValueClient Connection Defaults / Shared Library Preloading: Upstream classification
Latest boot value , Valuellvmjit: llvmjit

Lifecycle

Fact	Value
First observed	PG11
Present in	PG11–19 Beta 3
Removed in	No
Introduction commit	`432bb9e04da4` — Basic JIT provider and error handling infrastructure.
Commit date	2018-03-21
Discussion	thread 1

Default history

Measured PG9.0–19 Beta 3 boot defaults
Versions	Raw `boot_val`	Unit	Human value
PG11–19 Beta 3	`llvmjit`	—	llvmjit

How it works

jit_provider selects the JIT provider. The named provider supplies PostgreSQL’s JIT implementation and must be binary-compatible; changing the provider requires a server restart.

jit_provider is a POSTMASTER-context setting: PostgreSQL reads it during server startup, and a configuration reload or session SET cannot activate a new value.

Library discovery and preloading interact with installed binary versions, extension control files, server or backend startup, and the module’s own GUCs.

Tuning advice

Tip

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

Workload	Guidance
OLTP	Do not switch jit_provider as routine tuning. Keep llvmjit when packaged and supported, and control whether JIT runs with jit and its cost thresholds.
OLAP	Evaluate a provider only with representative compilation time, execution speed, memory, package compatibility, and restart testing; provider choice is secondary to JIT thresholds.
Small nodes	Keep the packaged provider and usually control JIT use rather than replace its implementation; a missing provider can break startup or JIT execution.

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: PG11–19 Beta 3 unmodified; OLAP: PG11–19 Beta 3 unmodified; CRIT: PG11–19 Beta 3 unmodified; TINY: PG11–19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.

Common pitfalls

Expecting a reload or SET to activate jit_provider, although it requires a controlled server restart.
Naming a missing or ABI-incompatible module and causing connection failure or a server that cannot start.
Treating a search or preload path as harmless even though it defines which native code the server trusts.
Changing jit_provider globally without a rollback plan and a client or operational compatibility test.

shared_preload_libraries · session_preload_libraries · local_preload_libraries · dynamic_library_path · extension_control_path