Unexplained High CPU usage

My daily user machine has been running fine for a few years until recently.

It's a xeon e3-1231 with 32gb ecc on a supermicro X10sl7 motherboard. 9 drives plus a parity for the array and 4 cache drives

It has 2 windows 10 vm's installed, although I normally only run 1. 2 instances of nextcloud with their associated collabora and swag dockers, and a few occasionally used dockers such as krusader.  There are also a number of plugins primarily to keep the system healthy.

 

Anyway all of this cruised along on an average cpu usage of 25% until recently.  Then something happened.  CPU usage started averaging 80 - 100%.  Jerky sound and video. System overheats.  Basically it became unusable.

 

I did some isolation tests. Turned off the vm's and the dockers and it was still using 60 - 70% whilst doing nothing.

If i stopped the array, it dropped to 1 - 2%

 

I upgraded the op sys from 6.83 to 6.9 rc2 and it pretty well flat lined at 100%.

 

I then started to look at the plugins. I did a bit of searching through the forums and singled out a couple of plugins.  Turned them off and removed them.  Still no good.

 

I then went full hog and removed all of the plugins bar community apps.

 

That fixed it.

 

I then reinstalled the plugins that I really needed, which was most of them and the system is still cruising at 22%.

 

Not a very technical way to solve a problem but it worked.

 

So I'm not really sure what the cause was.  The system has had continual upgrades since early version 6, so maybe there was a bit of old version plugins not playing nice with their later counterparts.

 

I have to say I'm really impressed with version 6.9.  Until now I was going to hang off installing until the official release.  It is too good to go back.

Pass through is brilliant since incorporating the VFIO plugin and I have been longing to separate the file cache from the appdata/vms for quite a while.  I created a second cache whilst trying to solve this problem after going to 6.9.   Brilliant.