From: Alin Dobra <adobra@cise.ufl.edu>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: I/O throughput problem in newer kernels
Date: Tue, 7 Apr 2009 08:58:34 -0400 [thread overview]
Message-ID: <c5764b870904070558u51ec2e82ob26c8aabb2976f4e@mail.gmail.com> (raw)
In-Reply-To: <20090407003524.41c9b666.akpm@linux-foundation.org>
Andrew (and other people interestead),
I forgot to mention in the post that I used O_DIRECT for all tests
(including dd tests). The CPU utilization is negligible; keep in mind
that the machine has 32 cores so cpu should not be problem, or memory
bandwidth for that matter. The think that puzzles me the most is the
fact that the throughput does not level up, it goes down dramatically
(a factor of 3 for 54 hard drives versus 20 hard drives).
Alin
--
Alin Dobra
Assistant Professor
Computer Information Science & Engineering Department
University of Florida
prev parent reply other threads:[~2009-04-07 12:58 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-02 15:06 I/O throughput problem in newer kernels adobra
2009-04-07 7:35 ` Andrew Morton
2009-04-07 12:58 ` Alin Dobra [this message]
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