client_min_messages

client_min_messages is the PostgreSQL setting that defines the message levels that are sent to the client.

Note

Fact — official short description: “Sets the message levels that are sent to the client.”

Identity

Type , Valueenum: Upstream pg_settings type
Context , Valueuser: Settable by an ordinary user
Unit , Value—: Raw unit
Range , Value—: Raw limits in the last observed version
Enum values , Valuedebug5, debug4, debug3, debug2, debug1, log, notice, warning, error: — for non-enum types
Category , ValueClient Connection Defaults / Statement Behavior: Upstream classification
Latest boot value , Valuenotice: notice

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	`notice`	—	notice

How it works

client_min_messages sets the message levels that are sent to the client. Each level includes all the levels that follow it. The later the level, the fewer messages are sent. The threshold governs messages returned to the client, not messages written to the server log, and INFO is delivered regardless of the chosen threshold.

client_min_messages is a USER-context setting. An authorized role can change it for a session, while ALTER ROLE or ALTER DATABASE can establish a default for future sessions.

It affects the client protocol’s diagnostic stream, while log_min_messages and log_min_error_statement independently control server-side records; INFO remains a special always-sent level.

Tuning advice

Tip

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

Workload	Guidance
OLTP	Set client_min_messages from the application’s diagnostic contract. Keep actionable warnings visible and change the threshold per role or session rather than muting an entire cluster.
OLAP	Analytical and interactive users may prefer NOTICE output, but batch pipelines should explicitly choose the messages they can parse without treating notices as result rows.
Small nodes	Leave the default NOTICE unless client chatter is measured as a problem; suppressing messages does not materially increase server capacity.

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: PG9.0–19 Beta 3 unmodified; OLAP: PG9.0–19 Beta 3 unmodified; CRIT: PG9.0–19 Beta 3 unmodified; TINY: PG9.0–19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.

Common pitfalls

Changing client_min_messages in one session and assuming role defaults, database defaults, or other pooled sessions changed with it.
Copying severity expectations from log_min_messages even though the client ordering treats LOG differently and always sends INFO.
Suppressing warnings globally and hiding deprecations or operational guidance that applications should surface.
Changing client_min_messages globally without a rollback plan and a client or operational compatibility test.

log_min_messages · log_min_error_statement · log_min_duration_statement · log_min_duration_sample · log_statement_sample_rate · log_transaction_sample_rate