Date: Mon, 27 Aug 2007 15:11:38 -0500
From: Decibel! <decibel@decibel.org>
To: Merlin Moncure <mmoncure@gmail.com>
Cc: postgresql performance list <pgsql-performance@postgresql.org>
Subject: Re: asynchronous commit feature
Message-ID: <20070827201138.GM54309@nasby.net>
References: <b42b73150708230609m4c48f7eel6aa92db4e1f10b13@mail.gmail.com>
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On Thu, Aug 23, 2007 at 09:09:00AM -0400, Merlin Moncure wrote:
> I'm testing the new asynch commit feature on various raid
> configurations and my early findings is that it reduces the impact of
> keeping wal and data on the same volume.  I have 10 disks to play
> with, and am finding that it's faster to do a 10 drive raid 10 rather
> than 8 drive raid 10 + two drive wal.
>=20
> anybody curious about the results, feel free to drop a line.  I think
> this will be a popular feature.

With or without a write cache on the RAID controller? I suspect that for
many systems, a write-caching controller will be very similar in
performance to async commit.
--=20
Decibel!, aka Jim Nasby                        decibel@decibel.org
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)

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