Date: Wed, 12 Sep 2007 15:47:23 +0100
From: Arjan van de Ven <arjan@infradead.org>
To: "Venkat Subbiah" <venkats@cranite.com>
Cc: <linux-kernel@vger.kernel.org>
Subject: Re: irq load balancing
Message-ID: <20070912154723.3d870787@laptopd505.fenrus.org>
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On Tue, 11 Sep 2007 16:18:15 -0700
"Venkat Subbiah" <venkats@cranite.com> wrote:

> Most of the load in my system is triggered by a single ethernet IRQ.
> Essentially the IRQ schedules a tasklet and most of the work is done
> in the taskelet which is scheduled in the IRQ. From what I read looks
> like the tasklet would be executed on the same CPU on which it was
> scheduled. So this means even in an SMP system it will be one
> processor which is overloaded.
> 
> So will using the user space IRQ loadbalancer really help? What I am
> doubtful about is that the user space load balance comes along and
> changes the affinity once in a while. But really what I need is every
> interrupt to go to a different CPU in a round robin fashion.

if you round robin network interrupts your performance will be really
really bad....
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