From: Tom Lane <tgl@sss.pgh.pa.us>
To: Guillaume Cottenceau <gc@mnc.ch>
Cc: pgsql-performance@postgresql.org
Subject: Re: 7 hrs for a pg_restore?
Date: Thu, 21 Feb 2008 13:09:32 -0500
Message-ID: <13059.1203617372@sss.pgh.pa.us> (raw)
In-Reply-To: <87ablu5icl.fsf@mnc.ch>
References: <200802191303.58840.doug@hunley.homeip.net>
<47BB1C51.6010203@archonet.com>
<19241.1203445378@sss.pgh.pa.us>
<F80D4D50-9F3F-4CAA-B01E-B644912126D7@torgo.978.org>
<87ablu5icl.fsf@mnc.ch>
Guillaume Cottenceau <gc@mnc.ch> writes:
> I have made a comparison restoring a production dump with default
> and large maintenance_work_mem. The speedup improvement here is
> only of 5% (12'30 => 11'50).
> Apprently, on the restored database, data is 1337 MB[1] and
> indexes 644 MB[2][2]. Pg is 8.2.3, checkpoint_segments 3,
> maintenance_work_mem default (16MB) then 512MB, shared_buffers
> 384MB. It is rather slow disks (Dell's LSI Logic RAID1), hdparm
> reports 82 MB/sec for reads.
The main thing that jumps out at me is that boosting checkpoint_segments
would probably help. I tend to set it to 30 or so (note that this
corresponds to about 1GB taken up by pg_xlog).
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, gc@mnc.ch
Subject: Re: 7 hrs for a pg_restore?
In-Reply-To: <13059.1203617372@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox