Pthread_setschedparam failed due to operation not permitted

[ting.chang]

Hi all,

I’ve added below line into /etc/security/limits.conf in order to get permission to prioritize the thread.

 <username>    -     rtprio    98

Before nvidia-jetpack was installed, it worked perfectly.
But after I installed the nvidia-jetpack, the function pthread_setschedparam failed with the error "Failed to set schedule parameters: Operation not permitted"

In this case, if I change /proc/sys/kernel/sched_rt_runtime_us from default 950000 to -1, it will work. But this workaround is dangerous so I don’t want to use.

Why this issue comes with jetpack installed? Any patch to avoid this?

BTW, the environment is AGX Orin with L4T R35.4.1
Thank you.

[DaneLLL]

Hi,
Please disable CONFIG_RT_GROUP_SCHED, rebuild/replace kernel image and try again.

[ting.chang]

@DaneLLL

CONFIG_RT_GROUP_SCHED

Are there any side-effect after CONFIG_RT_GROUP_SCHED is disabled?

[ting.chang]

Hi all,

I found the alternative way of CONFIG_RT_GROUP_SCHED is to change the cgroup tasks.
After I manually add current shell PID ($$) into cgroup task, it works.

echo $$ | sudo tee /sys/fs/cgroup/cpu/tasks

Is it a bug? Why this happens only when JetPack installed?
Before JetPack is installed, the PID is automatically added into cgroup tasks if /etc/security/limits.conf is configured.
After JetPack is installed, the PID is NOT added into cgroup tasks.

[DaneLLL]

Hi,
Probably some of our packages(probably CUDA or TensorRT) have conflict with it. We would need to check further. Your solution looks fine. Please adopt it and thanks for the sharing.