AltinayGrass
commented
1 year ago After some search, I found cyclictest should run -s -n option at same time. Only -s cause some problem to use ctrl-c. By the way I was using ctrl-z to reach terminal it means cyclictest still running at the background.
In my case for the better performance cpu_dma_latency should be zero
Hello, This is not issue but may be better to know. I am testing ethercat IGH master program with 2ms cyclic intervals typical command like below.
taskset -c 3,7 sudo chrt -f 99 ./servo_pos 1000While cyclictest running with following arguments
sudo ~/rt-tests/cyclictest -a -t -n -p99at the background (in another terminal window) my period chancing between (198000-201000ns). But without cyclictest running, it is chancing between(189000-212000ns). There is an interesting behavior also which is if I run cyclictest with
sudo ~/rt-tests/cyclictest -a -t -s -p99and cut the process (not easy with ctrl-c) there is better result on our period also in cyclictest results.
PS: Kernel is Linux upx2 5.15.133-rt69 #4 SMP PREEMPT_RT Thu Oct 12 08:32:32 +03 2023 x86_64 x86_64 x86_64 GNU/Linux on Ubuntu 20.04