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From: "Alexander V. Lukyanov" <lav@netis.ru>
To: Theodore Tso <tytso@mit.edu>, linux-kernel@vger.kernel.org
Subject: Re: 2.6.29.1 vs 2.6.27.21 ext4 performance problem
Date: Mon, 13 Apr 2009 08:54:52 +0400	[thread overview]
Message-ID: <20090413045452.GA16038@night.netis.ru> (raw)
In-Reply-To: <20090410163620.GA14814@mit.edu>

On Fri, Apr 10, 2009 at 12:36:20PM -0400, Theodore Tso wrote:
> Does the differences go away if you do echo 0 into
> /sys/fs/ext4/<dev>/inode_readahead_blks?

Yes! Thanks for the tip. I think the problem here is that there
are lots of files (2M per file system) and the access is random.

> Are you seeing an increase in time, or decrease in transactions per
> second, or just that there is is an increase in read rates?

Load average goes up from 6 to 30, and request latency increases.

-- 
   Alexander..

      reply	other threads:[~2009-04-13  5:35 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-10 15:12 2.6.29.1 vs 2.6.27.21 ext4 performance problem Alexander V. Lukyanov
2009-04-10 16:36 ` Theodore Tso
2009-04-13  4:54   ` Alexander V. Lukyanov [this message]

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