Message-ID: <47CFDF55.6030103@yandex.ru>
Date: Thu, 06 Mar 2008 15:11:01 +0300
From: Dmitry Antipov <dmantipov@yandex.ru>
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To: Nick Piggin <nickpiggin@yahoo.com.au>
CC: Eric Dumazet <dada1@cosmosbay.com>, David Miller <davem@davemloft.net>,
       linux-kernel@vger.kernel.org
Subject: Re: Are Linux pipes slower than the FreeBSD ones ?
References: <1389671204703217@webmail34.yandex.ru> <20080305.000014.245410231.davem@davemloft.net> <47CE6C41.3090303@cosmosbay.com> <200803060120.38032.nickpiggin@yahoo.com.au>
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Nick Piggin wrote:

> One thing to try is pinning both processes on the same CPU. This
> may be what the FreeBSD scheduler is preferring to do, and it ends
> up being really a tradeoff that helps some workloads and hurts
> others. With a very unscientific test with an old kernel, the
> pipe.c test gets anywhere from about 1.5 to 3 times faster when
> running it as taskset 1 ./pipe

Sounds interesting. What kernel version did you tried? Can you
send your .config to me?

I've tried this trick on 2.6.25-rc4, and got ~20% more throughput for
large (> 8K) buffers at the cost of going ~30% down for the small ones.

Dmitry
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