From: Alan Hodgson <ahodgson@simkin.ca>
To: pgsql-performance@postgresql.org
Subject: Re: Experience with HP Smart Array P400 and SATA drives?
Date: Fri, 5 Dec 2008 15:30:01 -0800
Message-ID: <200812051530.01258@hal.medialogik.com> (raw)
In-Reply-To: <49395B57.EE98.0025.0@wicourts.gov>
References: <4934FE60.30702@sime.com>
<49395B57.EE98.0025.0@wicourts.gov>
> >>> Mario Weilguni <mweilguni@sime.com> wrote:
> > strange values. An individual drive is capable of delivering 91
> > MB/sec
>
> > sequential read performance, and we get values ~102MB/sec out of a
> > 8-drive RAID5, seems to be ridiculous slow.
What command are you using to test the reads?
Some recommendations to try:
1) /sbin/blockdev --setra 2048 device (where device is the partition or LVM
volume)
2) Use XFS, and make sure your stripe settings match the RAID.
Having said that, 102MB/sec sounds really low for any modern controller with
8 drives, regardless of tuning or filesystem choice.
--
Corporations will ingest natural resources and defecate garbage until all
resources are depleted, debt can no longer be repaid and our money becomes
worthless - Jay Hanson
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To: pgsql-performance@postgresql.org
Cc: ahodgson@simkin.ca
Subject: Re: Experience with HP Smart Array P400 and SATA drives?
In-Reply-To: <200812051530.01258@hal.medialogik.com>
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