Re: Question on CONFIG_IRQBALANCE / 2.6.x

From: Joerg Sommrey
Date: Fri Feb 18 2005 - 17:59:30 EST


On Fri, Feb 18, 2005 at 02:39:49PM -0800, Martin J. Bligh wrote:
> >
> > there's something I don't understand: With IRQBALANCE *enabled* almost
> > all interrupts are processed on CPU0. This changed in an unexpected way
> > after disabling IRQBALANCE: now all interrupts are distributed uniformly
> > to both CPUs. Maybe it's intentional, but it's not what I expect when a
> > config option named IRQBALANCE is *disabled*.
> >
> > Can anybody comment on this?
>
> If you have a Pentium 3 based system, by default they'll round robin.
> If you turn on IRQbalance, they won't move until the traffic gets high
> enough load to matter. That's presumably what you're seeing.

It's an Athlon box that propably has the same behaviour. Just another
question on this topic: with IRQBALANCE enabled, almost all interupts
are routet to CPU0. Lately irq 0 runs on CPU1 and never returns to CPU0
- is there any obvious reason for that?

-jo

--
-rw-r--r-- 1 jo users 63 2005-02-18 23:29 /home/jo/.signature
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