CPUs at 100%

[DingHo]

For unknown reasons, my UnRAID server will suddenly have all 4 CPUs pegged to 100%.  The result is the whole house loses internet access as I've got Pi-hole DNS, and Unifi Controller dockers running on this box.  It happens about once a week.  I first thought it was the Pi-hole docker so I  pinned it to a single CPU.  Then I thought it was the Plex docker, so I pinned that to 2 CPUs.  Neither action has solved the problem.  Running top doesn't seem to indicate what is maxing out the CPUs, no process is using over ~20%.  I can fix it without rebooting by restarting the plex docker via command line.  I've been having this problem for almost a year.   I've looked at the diagnostics but can't figure this out.  Could anyone please help?

 

 

scour-diagnostics-20210430-0910.zip

[DingHo]

Occurred again today.  I noticed the cache drive was being read at a very high rate while CPUs were pegged to 100% again.

Attached new diags.

 

Any help appreciated.

scour-diagnostics-20210503-0959.zip

[JorgeB]

Looks more high load due to i/o wait, if you stop all cache activity (turn off docker service/VMs if needed to test) does it get better?

[DingHo]

16 hours ago, JorgeB said:

Looks more high load due to i/o wait, if you stop all cache activity (turn off docker service/VMs if needed to test) does it get better?

@JorgeB thanks for the reply.  
Is there anyway to check besides disabling docker/VMs? As this doesn’t occur predictably, and sometimes not for many days, I’d be without many services unless I built another system to take over network duties.

thanks again. 
 

[JorgeB]

I meant does it get better if you stop everything after the problem starts?

[DingHo]

Sorry, I misunderstood. 

If I restart only the plex docker, it goes back to normal operation.  I haven't tried disabling/re-enabling the docker service and VM service.

[JorgeB]

1 hour ago, DingHo said:

If I restart only the plex docker, it goes back to normal operation.

Sounds like a plex problem then, you can try the plex forum or the docker support thread.

[esaru]

Could it be the infamous Plex health check? AFAIK that issue is resolved in later versions of Unraid. May I ask why you are not upgrading? It seems like an easy thing to apply if you're having issues.