From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next-2.6] inetpeer: lower false sharing effect
Date: Wed, 08 Jun 2011 23:31:45 -0700 (PDT)
Message-ID: <20110608.233145.255635792817750847.davem@davemloft.net>
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Cc: netdev@vger.kernel.org, andi@firstfloor.org,
	tim.c.chen@linux.intel.com
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 09 Jun 2011 08:26:50 +0200

> Profiles show false sharing in addr_compare() because refcnt/dtime
> changes dirty the first inet_peer cache line, where are lying the keys
> used at lookup time. If many cpus are calling inet_getpeer() and
> inet_putpeer(), or need frag ids, addr_compare() is in 2nd position in
> "perf top".
> 
> Before patch, my udpflood bench (16 threads) on my 2x4x2 machine :
 ..
> After patch, no more addr_compare() in profiles :
 ..
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
> CC: Andi Kleen <andi@firstfloor.org>
> CC: Tim Chen <tim.c.chen@linux.intel.com>

Applied, thanks!