pg_partman — Partition Management

pg_partman automates partition creation and retention for native PostgreSQL partitioned tables. MonPG reads partman.part_config and per-table partition counts to surface:

• Partition count per parent table.
• Pre-creation lag — partman defaults to creating 4 partitions ahead, and we alert if it falls below 1 ahead. Less than 1 ahead means inserts are about to fail.
• Retention drop lag — partitions past their retention that haven't been dropped yet. Usually means the bgw is stopped.
• Background worker (pg_partman_bgw) status if it's running.

Enabling

Plain CREATE EXTENSION for the extension itself — pure DDL, no SPL needed. The pg_partman_bgw background worker requires SPL + restart, but it's optional. You can also call partman.run_maintenance() from external cron, pg_cron, or whatever scheduler you already have.

• RDS: PG 15+. CREATE EXTENSION pg_partman;.
• Azure Flex / Cloud SQL / Crunchy / Aiven: shipped, plain CREATE EXTENSION.
• Heroku: Standard+ only (Essential lacks it).
• Self-hosted: install pg_partman package + CREATE EXTENSION.

Bgw or cron

If your provider supports SPL changes, the bgw is simpler — auto-runs every pg_partman_bgw.interval seconds, no extra moving parts. If it doesn't, schedule with pg_cron or the equivalent:

SELECT cron.schedule('partman-maintenance', '*/30 * * * *',
  $$SELECT partman.run_maintenance()$$);

Either way produces the same result. The bgw is more convenient when it works; the cron approach is more portable.