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From: Anthony Liguori <aliguori@us.ibm.com>
To: Avi Kivity <avi@redhat.com>
Cc: Ryan Harper <ryanh@us.ibm.com>,
	qemu-devel@nongnu.org, kvm <kvm@vger.kernel.org>
Subject: [Qemu-devel] Re: [PATCH] Implement an fd pool to get real AIO with posix-aio
Date: Wed, 24 Sep 2008 09:17:07 -0500	[thread overview]
Message-ID: <48DA4BE3.30403@us.ibm.com> (raw)
In-Reply-To: <48DA021F.2050504@redhat.com>

Avi Kivity wrote:
> Anthony Liguori wrote:
>
> dup()ing the fd on each request is unnecessary work; would be better 
> to cache the duped fd.

Yeah, I was concerned about this too.  Ryan reran the fio benchmark and 
the submission latency and completion latency were identical to the 
linux-aio patches.  That suggests that the overhead of dup() is lost in 
the noise.

Since this is simpler and keeps the number of open file descriptors as 
low as possible, I was happy about that.

Regards,

Anthony Liguori

> Of course, if this is just a stepping stone, it doesn't matter very much.
>

      reply	other threads:[~2008-09-24 14:18 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-23 20:34 [Qemu-devel] [PATCH] Implement an fd pool to get real AIO with posix-aio Anthony Liguori
2008-09-24  9:02 ` [Qemu-devel] " Avi Kivity
2008-09-24 14:17   ` Anthony Liguori [this message]

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