diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index d95c218d39..aee8ff2dfb 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -825,6 +825,26 @@ analyze threshold = analyze base threshold + analyze scale factor * number of tu autovacuum_vacuum_cost_limit storage parameters have been set are not considered in the balancing algorithm. + + + Autovacuum workers generally don't block other commands. If a process + attempts to acquire a lock that conficts with the + SHARE UPDATE EXCLUSIVE lock held by autovacuum, lock + acquisition will interrupt the autovacuum. For conflicting lock modes, + see . However, if the autovacuum + is running to prevent transaction ID wraparound (i.e., the autovacuum query + name in the pg_stat_activity view ends with + (to prevent wraparound)), the autovacuum is not + automatically interrupted. + + + + + Regularly running commands that acquire locks conflicting with a + SHARE UPDATE EXCLUSIVE lock (e.g., ANALYZE) can + effectively prevent autovacuums from ever completing. + +