Re: stats collector process: WRDSK = WRDSK_CANCEL?

On Tue, Dec 22, 2009 at 10:30, Лев Ласкин <laskin82(at)gmail(dot)com> wrote:
> Hi.
> We have installed Postgresql 8.3.3. When we see the output of atop-d, we see
> just such a string
>
> db0: ~ # atop 15
> ATOP - db0 2009/12/22 12:14:29 15 seconds elapsed
> DSK | sda | busy 50% | read 72 | write 207 | avio 27 ms |
>
>   PID RDDSK WRDSK WRDSK_CANCEL DSK CMD 1 / 2
> 11296 0K 185.0M 185.0M 97% postgres
>
> db0: ~ # ps auxww | grep postgre
> postgres 11296 4.3 0.1 24244 13028? Ss Nov24 1734:25 postgres: stats
> collector process
>
> Why WRDSK = WRDSK_CANCEL? So it should be? Perhaps we were wrong in the
> settings.
>
> Who can help anything in this matter?

WRDSK_CANCEL is data that was written, but deleted before it was
flushed to disk. That is normal behaviour for the stats temp file,
which is written and deleted within half a second.

8.4 will do a lot less writes here, but on 8.4 it's perfectly normal.

--
Magnus Hagander
Me: http://www.hagander.net/
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