[Qemu-devel] Re: [PATCH 1/8] v2: introduce -numa command line option

[Andre Przywara]

Anthony Liguori wrote:
> > +        if (i == numnumanodes) {
> > +            for (i = 0; i < smp_cpus; i++)
> > +                node_to_cpus[i % numnumanodes] |= 1<<i;
> >   
>
> The way CPUs are allocate here seems strange?  Each CPU is assigned 
> round robin?  Should you have node 0 contain 1..X, node 1 contain X..Y, 
> node 2 contain Y..smp_cpus?
This is because an algorithm to do it this way is more complicated than 
this round-robin scheme (imagine distributing 8 CPUs over 3 nodes). 
Actually I know machines which do this natively (probably for the same 
reason, code simplicity in the BIOS). OSes can cope with my variant too, 
there is no guarantee that sequentially numbered CPUs belong to one node.
But if you insist, I fix it.

Regards,
Andre.

--
Andre Przywara
AMD-OSRC (Dresden)
Tel: x84917