PG-REC-BLOCKING-001 · Lock waits of 30 s or more during the recording

Severity	Confidence	Permission	Applies to
High	Confirmed	pg_monitor (pg_read_all_stats)	Recordings (codedb-lens record): PostgreSQL 14+, RDS, Aurora, Azure Flexible

What it checks

The locks collector (pg_stat_activity + pg_blocking_pids(), every 15 s). One episode per blocking backend while a session waits on a lock at least 30 s (min_wait_s).

Why it matters

Sessions waited at least 30 seconds for a lock held by another backend. Users see timeouts and frozen screens while it lasts.

Next action

Start with the blocker of the longest episode. A blocker "idle in transaction" is an application that opened a transaction and did not finish it; set idle_in_transaction_session_timeout and fix the application. An active blocker is a long statement to tune or move off-peak.

How to verify

Record again during the same hours after the fix. The episodes for that blocker must be gone or much shorter.

Limitations

Samples are taken every 15 seconds, so lock waits shorter than that may be missed, and an episode's length is accurate to about 15 seconds.