When logging to event log is enabled, this parameter determines the program name used to identify PostgreSQL messages in the log.
At a glance
| Property | Value |
|---|---|
| Parameter | event_source |
| Category | Error Reporting and Logging |
| Default | PostgreSQL |
| Value type | string |
| Change scope | Server restart required (postgresql.conf) |
| Available in | PostgreSQL 12, 13, 14, 15, 16, 17, 18, 19 (added in 12) |
What it does
When logging to event log is enabled, this parameter determines the program name used to identify PostgreSQL messages in the log. The default is PostgreSQL. This parameter can only be set at server start.
(Description quoted from the official PostgreSQL documentation.)
How to apply a change
Set it in postgresql.conf (or with ALTER SYSTEM) and restart the server — this parameter cannot change without a restart.
Inspect the current value and source with SHOW event_source; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'event_source';.
Tuning guidance
Tune this for observability versus log volume, not for raw performance. More verbose logging helps diagnose problems but costs disk and I/O; quieter logging saves space but hides detail. Pick a level your log pipeline can store and search, and raise verbosity temporarily when investigating an incident.