Re: [systemd-devel] Real-time scheduling doesn't work with StartupCPUWeight/CPUWeight
On 9/17/22 18:01, Lennart Poettering wrote: > Please consult README, look for comment on CONFIG_RT_GROUP_SCHED=n. Wow, thank you! Disabling group scheduling for realtime tasks did the trick. > Lennart Cheers, Robert
Re: [systemd-devel] Real-time scheduling doesn't work with StartupCPUWeight/CPUWeight
On Mi, 14.09.22 15:03, Robert Tiemann (r...@gmx.de) wrote: > Hi! > > I have optimized boot times for an embedded system by setting > StartupCPUWeight= and CPUWeight= for a few services. The startup > values are set to various values. All unit files I have touched also > contain the line "CPUWeight=100" so that the system is running with > defaults after startup. Some unit files contain Nice= assignments > (placed there before my optimizations, so I kept them in place). > > Now, the problem is with one process in the system which requires > real-time priorities. It calls pthread_setschedparam() to configure > two of its threads for SCHED_RR policy at priority 99. This used to > work before my optimizations, but now pthread_setschedparam() fails > with EPERM error. I have added LimitRTPRIO=infinity, but it still > doesn't work. The threads are created and configured after the startup > phase has finished. Please consult README, look for comment on CONFIG_RT_GROUP_SCHED=n. Lennart -- Lennart Poettering, Berlin
[systemd-devel] Real-time scheduling doesn't work with StartupCPUWeight/CPUWeight
Hi! I have optimized boot times for an embedded system by setting StartupCPUWeight= and CPUWeight= for a few services. The startup values are set to various values. All unit files I have touched also contain the line "CPUWeight=100" so that the system is running with defaults after startup. Some unit files contain Nice= assignments (placed there before my optimizations, so I kept them in place). Now, the problem is with one process in the system which requires real-time priorities. It calls pthread_setschedparam() to configure two of its threads for SCHED_RR policy at priority 99. This used to work before my optimizations, but now pthread_setschedparam() fails with EPERM error. I have added LimitRTPRIO=infinity, but it still doesn't work. The threads are created and configured after the startup phase has finished. Removing the StartupCPUWeight= and CPUWeight= lines from all unit files allows pthread_setschedparam() to succeed. It starts failing when setting StartupCPUWeight= even for a single, unrelated service. How can I have an optimized startup and still have real-time priorities in that process? The system is running systemd 250.5. Best regards, Robert
