NOHZ: local_softirq_pending 08

[slymanjojo]

Anybody have an idea what these message being written to dmesg?!

Linux Hell64 5.9.11-rockchip64 #20.11.1 SMP PREEMPT Fri Nov 27 21:59:08 CET 2020 aarch64 GNU/Linux

 

-snip-

[Wed Dec  9 04:37:51 2020] NOHZ: local_softirq_pending 08
[Wed Dec 16 22:54:43 2020] NOHZ: local_softirq_pending 08
[Thu Dec 17 02:35:38 2020] NOHZ: local_softirq_pending 08

 

Anything to be alarmed about?

[ShadowDance]

If you're seeing a few of those every now and then, nothing to be alarmed about. It can happen when the CPU is stressed and is normal. If you're constantly seeing it then you might want to consider either reducing the CPU load or disabling NOHZ.

 

For understanding what NOHZ does, I highly recommend this Stack Overflow answer to: "How NOHZ=ON affects do_timer() in Linux kernel?".

 

If you want to get rid of the message, you can simply add the following to /boot/armbianEnv.txt:

 

extraargs=nohz=off

 

But if you decide to do this, make sure you fully understand what it does by reading the aforementioned SO article and perhaps https://www.kernel.org/doc/Documentation/timers/NO_HZ.txt.

[slymanjojo]

@ShadowDance   Thanks for the reply.    I have not been getting many of these so I will keep monitoring this over the next few weeks.

 

- Not certain if it was related to recent testing I was doing with: Jellyfin it was chewing-up plenty of CPU even with direct play -I have un installed it.   Helos64 turns out to be a poor choice for streaming server (tested: emby, jellyfin, plexserver)

 

[SIGSEGV]

@slymanjojo

If you don't need the transcoding - the minidlna package could be a good alternative, low resource usage and the performance mostly will depend on your network and the reproduction device.

Once HW transcoding makes it to the latest kernels, the other packages should behave much better - you're not the only one waiting for it.