From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next-2.6] inetpeer: lower false sharing effect
Date: Fri, 10 Jun 2011 06:47:50 +0200
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To: David Miller <davem@davemloft.net>
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Le jeudi 09 juin 2011 =C3=A0 20:43 -0700, David Miller a =C3=A9crit :
> From: Tim Chen <tim.c.chen@linux.intel.com>
> Date: Thu, 09 Jun 2011 17:03:55 -0700
>=20
> > When I retest with original 3.0-rc2 kernel, inet_putpeer no longer =
shows
> > up, wonder if dst->peer was not set for some reason.=20
>=20
> The overhead will only show up if an inetpeer entry exists for
> the destination IP address.
>=20
> You can force one to be created, for example, by making a TCP
> connection to that destination.

Or sending big frames, to force ip fragmentation (we store the id
generator in inetpeer cache)