Re: [RFC][PATCH 0/5] Signal scalability series

Matt Fleming
2011-10-03T21:00:42Z

On Mon, 2011-10-03 at 18:35 +0200, Oleg Nesterov wrote:
> On 10/03, Matt Fleming wrote:
> >
> > Oh, are you referring to Oleg's email about the slow down under kvm?
> > Yeah, admittedly that's a pretty clear indicator that something is wrong
> > with the approach in this patch series.
>
> Or there was something wrong with my testing, please recheck. I specially
> mentioned I was surprised by the numbers. May be kvm, or lockdep...

No, I don't think there was anything wrong with your testing method. I
ran your command-line under Qemu and saw similar results - with the
patches applied the single-threaded case slows down (not by 50%, it
looks more like 25%, but that's still unacceptable and not at all what I
had anticipated).

--
Matt Fleming, Intel Open Source Technology Center