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Message-ID: <33c6269f0601181117j10bdeb27ke733c9b032e22cbc@mail.gmail.com>
Date: Wed, 18 Jan 2006 14:17:04 -0500
From: Alex Turner <armtuk@gmail.com>
To: Benjamin Arai <barai@cs.ucr.edu>
Subject: Re: 3WARE Card performance boost?
Cc: pgsql-performance@postgresql.org
In-Reply-To: <00ee01c61c5a$5db2c870$d7cc178a@uni>
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References: <00ee01c61c5a$5db2c870$d7cc178a@uni>

A 3ware card will re-order your writes to put them more in disk order,
which will probably improve performance a bit, but just going from a
software RAID 1 to a hardware RAID 1, I would not imagine that you
will see much of a performance boost.  Really to get better
performance you will need to add more drives, or faster drives.  If
you are currently running 7200 RPM consumer drives, going to a
10000RPM WD Raptor drive will probably increase performance by about
30%, again not all that much.

Alex

On 1/18/06, Benjamin Arai <barai@cs.ucr.edu> wrote:
>
> Hi,
>
> I am currently doing large weekly updates with fsync=3Doff.  My updates
> involves SELECT, UPDATE, DELETE and etc.  Setting fsync=3Doff works for m=
e
> since I take a complete backup before the weekly update and run a "sync" =
and
> "CHECKPOINT" after each weekly update has completed to ensure the data is
> all written to disk.
>
> Obviously, I have done this to improve write performance for the update e=
ach
> week.  My question is if I install a 3ware or similar card to replace my
> current software RAID 1 configuration, am I going to see a very large
> improvement?  If so, what would be a ball park figure?
>
>
> Benjamin Arai
> barai@cs.ucr.edu
> http://www.benjaminarai.com
>