On Thu, 2006-12-14 at 11:28, dev wrote: > Hello friends, > > we have some strange problem, postmaster (pg 8.1 /win32) > suddenly shutdown because of "no reason". > > The interesting thing is that this occurs always at > almost same time (between 0.00 and 0.30h), in that time period is > running system backup (Veristas backupexec agent) - starts at 23:30. > The problem occurs randomly. > In two of cases we have UPDATE/INSERT operation, but in third case - no. > > P.S. Why "autovacuum" runs every minute almost? Is this related? > > Thanks in advanced! > > > ================ LOG (2006-12-14) ================== > 2006-12-14 00:00:51 LOG: autovacuum: processing database "mtdb" > > 2006-12-14 00:01:52 LOG: autovacuum: processing database "mtdb" > > 2006-12-14 00:02:53 LOG: autovacuum: processing database "mtdb" > > 2006-12-14 00:03:54 LOG: autovacuum: processing database "mtdb" > > 2006-12-14 00:04:56 LOG: autovacuum: processing database "mtdb" > > 2006-12-14 00:06:02 LOG: autovacuum: processing database "mtdb" > > 2006-12-14 00:06:02 ERROR: could not write block 14725 of relation > 1663/16388/61387: Permission denied > > 2006-12-14 00:06:02 CONTEXT: writing block 14725 of relation > 1663/16388/61387
Looks like something is changing the permissions on this file or something. Is your backup agent (vertias backupexec) doing a file system backup of the $PGDATA directory? This is probably not a good idea, especially if it changes perms / locks the files while it is doing a backup. Either way, a file system backup is not the proper way to backup a pgsql instance, unless it is combined with PITR recovery. Best answer is to not let the backup agent hit the $PGDATA directory, but rather to run a backup with pg_dump or pg_dumpall to some other directory and have your backup agent back that file up.
