Re: Observational notice...

On Friday 12 December 2003 8:47 am, Scott Likens wrote:
> I've been observing my 5.2-RC box lately and it's running _ALOT_
> slower then it has previously.
>
> It has no ACPI throttling support, and quite frankly this is annoying
> me, my ubench marks have gone down over 3000 points.
>
> Granted this is a SMP machine, with or without ULE (using 4BSD) it
> makes no difference.
>
> it's like a slug on wheels.
>
> Has anyone else observed this? or is this a unique situation?
>
> This is a dual P2-450 with 1gig of Ecc (Xeon processor's)
>
> It's not exactly the greatest thing on the market, but I need it to
> work properly and this isn't good.
>
> any hints?  i've read the thread on acpi throttling, but I don't
> believe I fall into that catagory due to the age of the cpu.

This sounds similar to what I was seeing on my P2-400 SMP box.

Check "vmstat -i" to see if you have a massive amount of interrupts 
going on (mine were on IRC20, at a rate of about 45K).

I managed to "fix" this by applying the patch at 
http://www.FreeBSD.org/~jhb/patches/acpi_irq.patch
and rebuilding/installing the kernel. No more spurious interrupts, and 
performance is about the same as I used to have with 5.1R.

I have no idea if this patch has any side-effects, so at the moment I am 
treating it with extreme caution.

Of course, your problem could be totally different, and all this from me 
could be hot air :)

A.

-- 
Andy Fawcett                                     | andy_at_athame.co.uk
                                                 | tap_at_kde.org
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