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Date: Sun, 25 May 2008 17:12:06 +0200
From: "Francis Moreau" <francis.moro@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: question about splice performance
Cc: jens.axboe@oracle.com
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Hi,

I did a really basic benchmark and was suprise about the results.

$ echo 3 > /proc/sys/vm/drop_caches
$ time  splice-cp  vmlinux /tmp/vmlinux

real    0m10.158s
user    0m0.002s
sys     0m0.401s

$ echo 3 > /proc/sys/vm/drop_caches
$ time  cp  vmlinux /tmp/vmlinux

real    0m10.590s
user    0m0.017s
sys     0m0.459s


I was expecting splice-cp case to be faster.

Could someone enlight me ?

Thanks
-- 
Francis