[dpdk-dev] [PATCH v5] build: optional NUMA and cpu counts detection

[Piotr Kubaj]

Hi,

sorry for the late answer.

I suppose you mean sysctl command, not systemctl.

On dual CPU systems, it returns 2. On single CPU ones, 1.

On 21-08-03 10:21:50, Juraj Linkeš wrote:
> 
> 
> > -----Original Message-----
> > From: David Christensen <drc at linux.vnet.ibm.com>
> > Sent: Tuesday, August 3, 2021 1:29 AM
> > To: Juraj Linkeš <juraj.linkes at pantheon.tech>; thomas at monjalon.net;
> > david.marchand at redhat.com; bruce.richardson at intel.com;
> > Honnappa.Nagarahalli at arm.com; Ruifeng.Wang at arm.com;
> > ferruh.yigit at intel.com; jerinjacobk at gmail.com; jerinj at marvell.com;
> > stephen at networkplumber.org; Piotr Kubaj <pkubaj at FreeBSD.org>
> > Cc: dev at dpdk.org
> > Subject: Re: [PATCH v5] build: optional NUMA and cpu counts detection
> > 
> > 
> > 
> > On 8/2/21 5:44 AM, Juraj Linkeš wrote:
> > >> +if os.name == 'posix':
> > >> +    if os.path.isdir('/sys/devices/system/node'):
> > >> +        numa_nodes = glob.glob('/sys/devices/system/node/node*')
> > >> +        numa_nodes.sort()
> > >> +        print(int(os.path.basename(numa_nodes[-1])[4:]) + 1)
> > >> +    else:
> > >> +        subprocess.run(['sysctl', '-n', 'vm.ndomains'], check=False)
> > >> +
> > >
> > > Bruce, David, Thomas,
> > >
> > > Is DPDK actually supported on Power9 FreeBSD? Is anyone using this
> > combination? How can we address the open question of what exactly does
> > sysctl -n vm.ndomains return on a Power9 FreeBSD system? Or should we just
> > leave it as is? Or maybe add 1 to the output (as we do in other cases)?
> > 
> > Not supported within IBM, but you can buy OpenPOWER boxes from 3rd parties
> > such as Raptor Computing Systems so there may be customers using DPDK on
> > POWER with FreeBSD that I don't track.  Adding Piotr Kubaj who has commented
> > on POWER/FreeBSD issues in this past.
> > 
> > Dave
> 
> Thanks, David.
> 
> Piotr, to provide more context, we're trying to figure out what the highest NUMA node on a system is.
> On P9 systems, here's how NUMA nodes look like in Linux:
> 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):
> The highest NUMA with CPUs is node8.
> 
> We're trying to get the highest NUMA with CPUs on P9 FreeBSD systems, but we don't know whether FreeBSD NUMA layout looks the same (does FreeBSD report non-contiguous NUMA nodes as Linxu above, or does it renumerate) a what does "systemctl -n vm.ndomains" return. Could you check these for us?