"Andy Shellam" <andy.shellam@xxxxxxxxxxxxxxxxx> writes: > If pg_start_backup is used correctly, no data pages will be written to disk > until pg_stop_backup is called, so this shouldn't be an issue That's incorrect, the database will continue to operate normally. The only thing pg_start_backup really does is lay down a marker so you can tell how far back you need to save WAL files in order to do a PITR restore using your backup. The fact that the backup tool might get an inconsistent copy of some files is not an issue, because replay of the WAL files against the copied database will fix any inconsistencies. It definitely is a pain in the neck that GNU tar complains about files changing underneath it --- I've looked for a way to disable that, or at least reduce it to a warning instead of an error condition, but gtar doesn't seem to have such a switch. You should try alternative backup tools such as cpio or rsync. regards, tom lane
