On Mon, 16 Jan 2023, John Kacur wrote: > > On Thu, 12 Jan 2023, Sebastian Andrzej Siewior wrote: > > > numa_num_task_cpus() returns here > 100 CPUs while the system has only > > 32 populated. The BIOS assumes that I can probably use larger CPUs (with > > more cores) on the socket so the number of "configured CPUs" is rather > > high. > > For default configuration, only with the -S option, it makes sense to > > use the current affinity instead looking at the number of possible CPUs > > which could be brought online. It still depends on the affinity of the > > created threads if the additional CPUs can be used. In a container setup > > this may not be the case. > > > > Use sched_getaffinity() to figure out the number of possible CPUs. ... > > In cyclictest we have > > if (num_threads == -1) > num_threads = get_available_cpus(affinity_mask); > > > But the num_threads can be set to -1 in OPT_THREADS too, > not just for OPT_SMP A sane default for --smp, which is almost-always used in sane cyclictest invocations, is still valuable IMHO. Thanks, -- Ahmed S. Darwish Linutronix GmbH
