From: Alvaro Herrera <alvherre@commandprompt.com>
To: Brad Nicholson <bnichols@ca.afilias.info>
Cc: Greg Smith <gsmith@gregsmith.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Long Running Commits - Not Checkpoints
Date: Thu, 13 Sep 2007 13:07:19 -0400
Message-ID: <20070913170719.GC1716@alvh.no-ip.org> (raw)
In-Reply-To: <1189702341.8624.38.camel@bnicholson-desktop>
References: <1189692915.8624.22.camel@bnicholson-desktop>
<Pine.GSO.4.64.0709131149390.20144@westnet.com>
<1189700385.8624.32.camel@bnicholson-desktop>
<1189702341.8624.38.camel@bnicholson-desktop>
Brad Nicholson wrote:
> On Thu, 2007-09-13 at 12:19 -0400, Brad Nicholson wrote:
> > On Thu, 2007-09-13 at 12:12 -0400, Greg Smith wrote:
> > > On Thu, 13 Sep 2007, Brad Nicholson wrote:
> >
> > > I'd be curious to see how you've got your background writer configured to
> > > see if it matches situations like this I've seen in the past. The
> > > parameters controlling the all scan are the ones you'd might consider
> > > turning down, definately the percentage and possibly the maxpages as well.
> >
> >
> > bgwriter_delay = 50 # 10-10000 milliseconds between
> > rounds
> > bgwriter_lru_percent = 20.0 # 0-100% of LRU buffers
> > scanned/round
> > bgwriter_lru_maxpages = 300 # 0-1000 buffers max
> > written/round
> > bgwriter_all_percent = 20 # 0-100% of all buffers
> > scanned/round
> > bgwriter_all_maxpages = 600 # 0-1000 buffers max
> > written/round
>
> I should add, there are 6 back ends running on this disk array
> (different servers and different data partitions) with these bgwriter
> settings.
Maybe it is running deferred triggers or something?
--
Alvaro Herrera http://www.advogato.org/person/alvherre
"I suspect most samba developers are already technically insane...
Of course, since many of them are Australians, you can't tell." (L. Torvalds)
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To: pgsql-performance@postgresql.org
Cc: alvherre@commandprompt.com, bnichols@ca.afilias.info, gsmith@gregsmith.com
Subject: Re: Long Running Commits - Not Checkpoints
In-Reply-To: <20070913170719.GC1716@alvh.no-ip.org>
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