From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: small RPS cache for fragments?
Date: Tue, 17 May 2011 23:00:50 +0200
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To: David Miller <davem@davemloft.net>
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Le mardi 17 mai 2011 =C3=A0 16:49 -0400, David Miller a =C3=A9crit :
> From: Tom Herbert <therbert@google.com>
> Date: Tue, 17 May 2011 13:02:25 -0700
>=20
> > I like it!  And this sounds like the sort of algorithm that NICs mi=
ght
> > be able to implement to solve the UDP/RSS unpleasantness, so even
> > better.
>=20
> Actually, I think it won't work.  Even Linux emits fragments last to
> first, so we won't see the UDP header until the last packet where it'=
s
> no longer useful.
>=20
> Back to the drawing board. :-/

Well, we could just use the iph->id in the rxhash computation for frags=
=2E

At least all frags of a given datagram should be reassembled on same
cpu, so we get RPS (but not RFS)