Re: checkpoint_timeout

Hi there.
I increased the wal_buffers and no change made.
I'm beggining to think that my problem is not related to "checkpoint & cia"
as I said early.
I have decreased the checkpoint_timeout to 3 min and the slow down
continuin' ocorring after each 5 min.

In this "slowdown" the postgres does nothing, it's simply stop doing the
operations. The softwares still waiting for the response.
This is a dedicated server, the only program another postgres that runs is
Slony-I

2008/10/8 Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>

> On Wed, Oct 8, 2008 at 12:08 PM, Kevin Grittner
> <Kevin(dot)Grittner(at)wicourts(dot)gov> wrote:
> >
> > If the problem is checkpoints (which seems likely but far from a sure
> > thing based on the information provided), aggressive background writer
> > setting might be your best bet under 8.2.X. To solve similar problems
> > we had to go to the following, although many on these lists feel that
> > settings this aggressive are rarely needed, so use at your own risk.
> >
> > #bgwriter_delay = 200ms
> > bgwriter_lru_percent = 20.0
> > bgwriter_lru_maxpages = 200
> > bgwriter_all_percent = 10.0
> > bgwriter_all_maxpages = 600
>
> I've tuned an 8.2 server with settings similar to this, and it made a
> world of difference on smoothing out performance. Note that bgwriter
> tends to use cpu and memory bandwidth up, so avoid going crazy on it.
>
> > Even better would be to go to the latest revision of the 8.3 release,
> > which at this writing is 8.3.4. In that release PostgreSQL spreads
> > out the work of a checkpoint to minimize this problem.
>
> Seconded. A lot of hard work went into making the bgwriter much
> easier to adjust, and much less likely to even need adjusting in 8.3.
>