From: Josh Berkus <josh@agliodbs.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: checkpoint segments
Date: Mon, 16 May 2005 09:17:20 -0700
Message-ID: <200505160917.20367.josh@agliodbs.com> (raw)
In-Reply-To: <20050516044053.GB9292@surnet.cl>
References: <07FDEE0ED7455A48AC42AC2070EDFF7C74609A@corpsrv2.tazznetworks.com>
<200505152026.02262.josh@agliodbs.com>
<20050516044053.GB9292@surnet.cl>
Alvaro,
> > Yes, and yes. Simply allocating more checkpoint segments (which can eat
> > a lot of disk space -- requirements are 16mb*(2 * segments +1) ) will
> > prevent this problem.
>
> Hmm? I disagree -- it will only make things worse when the checkpoint
> does occur.
Unless you allocate enough logs that you don't need to checkpoint until the
load is over with. In multiple data tests involving large quantities of
data loading, increasing the number of checkpoints and the checkpoint
interval has been an overall benefit to overall load speed. It's possible
that the checkpoints which do occur are worse, but they're not enough worse
to counterbalance their infrequency.
I have not yet been able to do a full scalability series on bgwriter.
--
Josh Berkus
Aglio Database Solutions
San Francisco
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To: pgsql-performance@postgresql.org
Cc: josh@agliodbs.com
Subject: Re: checkpoint segments
In-Reply-To: <200505160917.20367.josh@agliodbs.com>
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