From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: TCP_STREAM performance regression on commit b3613118
Date: Fri, 17 Feb 2012 13:33:27 -0500 (EST)
Message-ID: <20120217.133327.1178765872497293871.davem@davemloft.net>
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Cc: alex.shi@intel.com, linux-kernel@vger.kernel.org,
	tim.c.chen@intel.com, ying.huang@intel.com, netdev@vger.kernel.org
To: eric.dumazet@gmail.com
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=46rom: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 17 Feb 2012 10:50:39 +0100

> Le vendredi 17 f=E9vrier 2012 =E0 16:18 +0800, Alex,Shi a =E9crit :
>> The tcp_stream loop back performance has about 10% drop on the
>> commitment on our core2 2 sockets server. This commit has 2
>> parents(7505afe28, 5983fe), but both of them have no regression. So
>> guess the impact just happened when this 2 parents joint. That beyon=
d
>> our capability to dig it more.
>>=20
>> Any ideas?=20
>=20
> Most probably the more accurate truesize determination is responsible=
 of
> this tcp regression, since some prior assumptions might be wrong.
>=20
> Want to give more information on the workload ?
> Is it a 32 or 64 bit kernel ?

And let's start CC:'ing netdev too.