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From: "dada1" <dada1@cosmosbay.com>
To: "Andi Kleen" <ak@suse.de>
Cc: "Andi Kleen" <ak@suse.de>, "Simon Kirby" <sim@netnation.com>,
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Subject: Re: Longstanding networking / SMP issue? (duplextest)
Date: Thu, 20 Feb 2003 12:03:06 +0100
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> > Yes IP is best-effort. But this argument cant explain why IP on linux
works
> > better if we disable SMP on linux...
>
> It has nothing to do with SMP. The lazy locking dropping packets can
happen
> on UP kernels too in extreme cases. Also with preempt.
>

Well, I too noticed that binding NIC IRQS one one CPU

echo 1 > /proc/irq/18/smp_affinity

helps a lot in normal cases.

Some of us want SMP machine because application needs a lot of CPU, but we
also need to not drop frames to save the limited network bandwith.

Thanks

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