On Tue, Aug 31, 2021 at 07:54:16AM +0000, Juraj Linkeš wrote:
>
>
> > -----Original Message-----
> > From: Piotr Kubaj <[email protected]>
> > Sent: Tuesday, August 31, 2021 2:55 AM
> > To: Juraj Linkeš <[email protected]>
> > Cc: David Christensen <[email protected]>; [email protected];
> > [email protected]; [email protected];
> > [email protected]; [email protected];
> > [email protected]; [email protected]; [email protected];
> > [email protected]; [email protected]
> > Subject: Re: [PATCH v5] build: optional NUMA and cpu counts detection
> >
> > Hi,
> >
> > sorry for the late answer.
>
> Thanks for the answer anyway, better late than never.
>
> >
> > I suppose you mean sysctl command, not systemctl.
> >
>
> That's right. What does lscpu say? Are the NUMA nodes non-contiguous like
> this?:
> NUMA node0 CPU(s): 0-63
> NUMA node8 CPU(s): 64-127
> NUMA node252 CPU(s):
> NUMA node253 CPU(s):
> NUMA node254 CPU(s):
> NUMA node255 CPU(s):
>
> > On dual CPU systems, it returns 2. On single CPU ones, 1.
>
> I asked the previous question so that we know the actual numa node number of
> the second CPU. If it's 8, then sysctl does some renumeration and we can't
> use it.
>
> Bruce, maybe we should just parse lscpu output? That introduces a dependency,
> but that may not be such a big deal as lscpu is pretty common.
>
Until we are sure that we need it, can we just keep things simple? Perhaps
we can use lscpu if present, and fallback to sysctl output if not.
