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Subject: Re: [PATCH] genirq: Set initial default irq affinity to just CPU0
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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> What does this all mean to my GigE (dual 1.1 GHz 7455s)? Is this
> thing supposed to be able to spread irq between its cpus?

Depends on the interrupt controller. I don't know that machine
but for example the Apple Dual G5's use an MPIC that can spread
based on an internal HW round robin scheme. This isn't always
the best idea tho for cache reasons... depends if an at what level
your caches are shared between CPUs.

Ben.