Обсуждение: Old pg_xlog files

On Mar 22, 2006, at 1:37 PM, Tass Chapman wrote:

> Checkpoints appear to be up to date (via pg_controldata), but the
> pg_xlog directory has 95 files, of which 90 are dated before
> midnight yesterday or earlier.
>
> Can I just delete them safely? Or is there some recovery method I
> can do?
>

no, do not delete them.  they will eventually be re-used.  check back
in a few days and see how old the various files are...

Vivek Khera <vivek@khera.org> writes:
> On Mar 22, 2006, at 1:37 PM, Tass Chapman wrote:
>> Checkpoints appear to be up to date (via pg_controldata), but the
>> pg_xlog directory has 95 files, of which 90 are dated before
>> midnight yesterday or earlier.
>>
>> Can I just delete them safely? Or is there some recovery method I
>> can do?

> no, do not delete them.  they will eventually be re-used.  check back
> in a few days and see how old the various files are...

If there are more than about 2*checkpoint_segments of them, the extras
will be removed by the next successful checkpoint.  So there's really no
reason to touch them manually.

            regards, tom lane

"Tass Chapman" <tasseh.postgres@gmail.com> writes:
> Any suggestions on what I can look at to see why the checkpoint was so far
> outstanding and why it hung on in a Zombie state when we tried a soft boot?

If it was in a funny process state, I'd guess that there was some
hardware problem that caused a disk write request to hang up.  You
can get stuck in uninterruptible disk wait for quite a long time if
the disk doesn't respond.

            regards, tom lane

Thanks.
I'll see if I can get a scheduled maintenance check on this.

The disks seem to be good as they are a 0+1 RAID  and all internal tests show them to be in good health along with the controller. Would memory be a good suspect?