Date: Tue, 19 Dec 2006 21:15:51 -0800 (PST)
Message-Id: <20061219.211551.112620476.davem@davemloft.net>
To: shemminger@osdl.org
Cc: herbert@gondor.apana.org.au, mingo@elte.hu, akpm@osdl.org, wenji@fnal.gov,
       netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Bug 7596 - Potential performance bottleneck for Linxu TCP
From: David Miller <davem@davemloft.net>
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From: Stephen Hemminger <shemminger@osdl.org>
Date: Tue, 19 Dec 2006 21:11:24 -0800

> It was the realtime/normal comments that piqued my interest.
> Perhaps we should either tweak process priority or remove
> the comments.

I mentioned that to Linus once and he said the entire
idea was bogus.

With the recent tcp_recvmsg() preemption issue thread,
I agree with his sentiments even more than I did previously.

What needs to happen is to liberate the locking so that
input packet processing can occur in parallel with
tcp_recvmsg(), instead of doing this bogus backlog thing
which can wedge TCP ACK processing for an entire quantum
if we take a kernel preemption while the process has the
socket lock held.
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