Re: Recovery target 'immediate'

On Fri, Apr 19, 2013 at 3:11 AM, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com
> wrote:

> I just found out that if you use continuous archiving and online backups,
> it's surprisingly difficult to restore a backup, without replaying any more
> WAL than necessary.
>
> If you don't set a recovery target, PostgreSQL will recover all the WAL it
> finds. You can set recovery target time to a point immediately after the
> end-of-backup record, but that's tricky. You have to somehow find out the
> exact time when the backup ended, and set it to that. But if you set it any
> too early, recovery will abort with "requested recovery stop point is
> before consistent recovery point" error. And that's not quite precise
> anyway; not all record types carry timestamps, so you will always replay a
> few extra records until the first timestamped record comes along. Setting
> recovery_target_xid is similarly difficult. If you were well prepared, you
> created a named recovery point with pg_create_restore_point() immediately
> after the backup ended, and you can use that, but that requires forethought.
>
> It seems that we're missing a setting, something like recovery_target =
> 'immediate', which would mean "stop as soon as consistency is reached". Or
> am I missing some trick?
>
+1. This will be really helpful. I don't know either of any good way to
stop immediately after a consistent point now without tricking a target
just after the end of backup.
--
Michael