Hello Daniel, On Thu, 23 Feb 2023 at 00:41, Prasad Pandit <ppandit@xxxxxxxxxx> wrote: > # trace-cmd record -p nop -e all -M 0x7FE -m 32000 --poll ~test/rt-tests/oslat --cpu-list 1-10 --duration 1h -w memmove -m 4K -T20 > .... > Maximum: 14 11 13 12 12 13 12 11 12 10 (us) > Max-Min: 13 10 12 11 11 12 11 10 11 9 (us) > Duration: 3599.986 3599.986 3599.987 3599.987 3599.986 3599.987 3599.986 3599.987 3599.986 3599.986 (sec) > > * Running oslat(1) with SCHED_OTHER priority via 'trace-cmd --poll' option, did not show the spike. Nonetheless, trace-cmd(1) logs show <idle>, ktimers/ and kworker/ threads running on isolated CPUs. > * Now running rtla-osnoise(1) test with SCHED_OTHER: > # rtla osnoise top -c 1-10 -d 6h -s 20 -T 20 -Po:0 -q -t Please see: -> https://0bin.net/paste/ShXHmdvu#D0XY-WxTKCzWTxgQ+lTFbx1nB2TP2w+T0Mp8PBXt9gu * rtla-osnoise(1) running for 6 hours with SCHED_OTHER and SCHED_FIFO, both did not report any spike above 20us. It's reporting occurrence of IRQs only, all other noise columns are zero(0). That's a little surprising!? Thank you. --- - Prasad