Date: Sun, 11 Sep 2011 18:51:21 -0400
From: Stephen Frost <sfrost@snowman.net>
To: Anthony Presley <anthony@resolution.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: RAID Controller (HP P400) beat by SW-RAID?
Message-ID: <20110911225121.GM12765@tamriel.snowman.net>
References: 
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* Anthony Presley (anthony@resolution.com) wrote:
> I was really hoping that with hardware RAID that something would be faster
> (loading times, queries, etc...).  What am I doing wrong?

ext3 and ext4 do NOT perform identically out of the box..  You might be
running into the write barriers problem here with ext4 forcing the RAID
controllers to push commits all the way to the hard drive before
returning (thus making the BBWC next to useless).

You might try w/ ext3 on the new system instead.

Also, the p800's are definitely better than the p400's, but I don't know
that it's the controller that's really the issue here..

	Thanks,

		Stephen

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