Re: Should *.backup files ever be removed from pg_xlog?
От | Bruce Momjian |
---|---|
Тема | Re: Should *.backup files ever be removed from pg_xlog? |
Дата | |
Msg-id | 200506070321.j573LWm17788@candle.pha.pa.us обсуждение исходный текст |
Ответ на | Re: Should *.backup files ever be removed from pg_xlog? (Tom Lane <tgl@sss.pgh.pa.us>) |
Список | pgsql-hackers |
Tom Lane wrote: > Bruce Momjian <pgman@candle.pha.pa.us> writes: > > When you do a pg_start_backup()/pg_stop_backup(), the *.backup files > > created in pg_xlog are never deleted. Is that intended? > > Yes. See the documentation. DBAs can delete 'em if they feel like, > but I don't see a strong argument for automatically removing 'em. > They aren't actually large ... I don't see anywhere in the documentation where we say you can get rid of them. I see this: For example, if the starting WAL file is 0000000100001234000055CD thebackup history file will be named something like0000000100001234000055CD.007C9330.backup.(The second number in the filename stands for an exact position within the WALfile, and canordinarily be ignored.) Once you have safely archived the file systembackup and the WAL segment files usedduring the backup (as specified inthe backup history file), all archived WAL segments with namesnumerically less areno longer needed to recover the file system backupand may be deleted. However, you should consider keeping several backupsetsto be absolutely certain that you are can recover your data. Keepin mind that only completed WAL segment filesare archived, so therewill be delay between running pg_stop_backup and the archiving of allWAL segment files neededto make the file system backup consistent. The "all archived WAL segments with names numerically less are no longer needed" I assume is talking about files in the archive location, not pg_xlog. Does this need clarifying? -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
В списке pgsql-hackers по дате отправления: