From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl@linux-foundation.org>
Subject: Re: Multicast packet loss
Date: Fri, 27 Feb 2009 14:45:27 -0500 (EST)
Message-ID: <alpine.DEB.1.10.0902271441220.9381@qirst.com>
References: <49833DBC.7040607@athenacr.com> <20090130200330.GA12659@hmsreliant.think-freely.org> <49837F56.2020502@athenacr.com> <49838213.90700@cosmosbay.com> <alpine.DEB.1.10.0902271340320.9381@qirst.com> <49A8375A.6000006@cosmosbay.com>
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Cc: Kenny Chang <kchang@athenacr.com>, netdev@vger.kernel.org
To: Eric Dumazet <dada1@cosmosbay.com>
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On Fri, 27 Feb 2009, Eric Dumazet wrote:

> Christoph Lameter a ?crit :
> > On Fri, 30 Jan 2009, Eric Dumazet wrote:
> >> 2.6.29-rc contains UDP receive improvements (lockless)
> >> Problem is multicast handling was not yet updated, but could be :)
> > When will that happen?
> When proven necessary :)
>
> Kenny problem is about scheduling storm. The extra spin_lock() in UDP
> multicast receive is not a problem.

My tests here show that 2.6.29-rc5 still looses ~5usec vs. 2.6.22 via
UDP. This would fix a regression.....