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From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v5] rfs: Receive Flow Steering
Date: Tue, 20 Apr 2010 17:39:22 +0200
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Cc: Changli Gao <xiaosuo@gmail.com>,
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To: Tom Herbert <therbert@google.com>
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Le mardi 20 avril 2010 =C3=A0 08:04 -0700, Tom Herbert a =C3=A9crit :

> Maybe for the purposes of RPS, but hash collisions could definitely b=
e
> an issue in RFS.  If two active connections hit the same rps_flow
> entry this may cause thrashing of those connections between CPUs.  I
> think your patch may increase the probability of this happening.
>=20

Good point.

I'll make a gathering of tcp tuples on a busy server over a day and try
to compute number of clashes we can get with and without the addr/port
swapping.