PostgreSQL — алерт когда autovacuum не двигается

#!/usr/bin/env bash
# /etc/cron.d/pg-autovacuum
# */15 * * * * postgres /opt/pg-autovacuum.sh

DB=${PGDATABASE:-postgres}
THRESH_MIN=${THRESH_MIN:-30}          # alert if any vacuum runs > 30 min

OLDEST=$(psql -At -d "$DB" -c "
  SELECT EXTRACT(EPOCH FROM (NOW() - query_start)) / 60
  FROM pg_stat_activity
  WHERE query LIKE 'autovacuum:%'
  ORDER BY query_start ASC
  LIMIT 1;
")

OLDEST_MIN=${OLDEST%.*}
[ -z "$OLDEST_MIN" ] && OLDEST_MIN=0

if [ "$OLDEST_MIN" -gt "$THRESH_MIN" ]; then
  TABLE=$(psql -At -d "$DB" -c "
    SELECT regexp_replace(query, 'autovacuum: VACUUM\s+', '')
    FROM pg_stat_activity
    WHERE query LIKE 'autovacuum:%'
    ORDER BY query_start ASC LIMIT 1;
  ")
  curl -fsS "$HEARTBEAT_URL" --data "vacuum_min=$OLDEST_MIN,table=$TABLE"
  exit 2
fi
echo "OK (oldest vacuum=${OLDEST_MIN}m)"