From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [RFC] Could we avoid touching dst->refcount in some cases ?
Date: Mon, 24 Nov 2008 15:36:11 -0800 (PST)
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=46rom: Andi Kleen <andi@firstfloor.org>
Date: Mon, 24 Nov 2008 12:27:09 +0100

> On Mon, Nov 24, 2008 at 11:14:29AM +0100, Eric Dumazet wrote:
> > Andi Kleen a =E9crit :
> > >Eric Dumazet <dada1@cosmosbay.com> writes:
> > >
> > >>tbench has hard time incrementing decrementing the route cache re=
fcount
> > >>shared by all communications on localhost.
> > >
> > >iirc there was a patch some time ago to use per CPU loopback devic=
es to=20
> > >avoid this, but it was considered too much a benchmark hack.
> > >As core counts increase it might stop being that though.
> >=20
> > Well, you probably mention Stephen patch to avoid dirtying other co=
ntended
> > cache lines (one napi structure per cpu)
>=20
> No that patch wasn't from Stephen. iirc it was from someone at SGI.

That's how I remember it too.