Re: [PATCH] NUMA-Q disable irqbalance

Andrea Arcangeli
2002-08-13T23:27:16Z

On Tue, Aug 13, 2002 at 05:29:50PM -0500, Andrew Theurer wrote:
> > 2.4.19-rc3aa3:
> >
> > No Balance Ingo IRQ Balance Andrea IRQ Balance
> > 794 Mbps 787 Mbps 792 Mbps
> >
> > With hyperthreading:
> >
> > No Balance Ingo IRQ Balance Andrea IRQ Balance
> > 773 Mbps 798 Mbps 809 Mbps

thanks again for running the above benchmarks.

> version is a little less aggressive and has less overhead, something I'd
> prefer in 2.5.

Second that of course, btw, the detailed explanataion of the changes I
did while merging it can be found on lse-tech.

it is also possible HZ/50 is too high frequency still, I didn't run any
extensive test on the reprogramming frequency. I would suggest to try
with HZ/10 too (so every 100msec instead of every 20msec).

BTW, the very same algorithm should also be shared by alpha, alpha never
had hardware irq balancing support, it's like a p4, and we do static
routing distribution choosed by the kernel at boot which is been pretty
good so far (better than mainline 2.4 on a p4 smp) but the irqblanace
algorithm should be better there too.

Andrea