Re: Odd performance results

From: Peter Zijlstra
Date: Wed Jul 13 2016 - 08:34:30 EST


On Wed, Jul 13, 2016 at 09:27:48AM -0300, Henrique de Moraes Holschuh wrote:
> On Wed, 13 Jul 2016, Ingo Molnar wrote:
> > > The ordering Paul has, namely 0,1 for core0,smt{0,1} is not something
> > > I've ever seen on an Intel part. AMD otoh does enumerate their CMT stuff
> > > like what Paul has.
> >
> > That's more the natural 'direct' mapping from CPU internal topology to CPU id:
> > what's close to each other physically is close to each other in the CPU id space
> > as well.
>
> But does it correctly reflect the hardware? That seems to be the real
> question...

Its just enumeration afaict. But its weird that this changed. Some BIOS
team somewhere changed things and I want to know why (and how widespread
this is).