Hi All,
I have a user level benchmark that does
for (i = 0; i < nthreads; i++)
(void) thr_create(NULL, 0, testaes, (void *)0,
THR_NEW_LWP, &tid);
I found that running this benchmark with nthreads == ncpus
schedules each thread to a separate CPU. The system is a Niagara 2
with 128 CPUs/strands.
However, for a kernel module/benchmark that does
for (i = 0; i < nthreads; i++)
(void) thread_create(NULL, 0, &process_aes, (void *)i, 0, &p0,
TS_RUN, minclsyspri);
the scheduling is very uneven and a whole set of CPUs from
64-127 did not have any thread scheduled on them. The distribution
among 0-63 is also uneven.
I assume the thread scheduling behavior is different for system threads
which do not have a LWP. But, is this not sub optimal? Is the
assumption that kernel subsystems that need to use a large number
of threads do their own CPU binding/scheduling to assure even distribution?
Thanks,
-Krishna
_______________________________________________
perf-discuss mailing list
perf-discuss@opensolaris.org
