Lots of system activity - how do I determine what's happening?

There is a lot of system activity on my PR4100 RAID 10 device but I am not running anything. I noticed it about an hour ago and the drives are actively engaged. The antivirus is due to run weekly but I noted that it paused 13% through, plus I got 133 emails about the anti virus run which seems excessive to me.

How can I go about finding out what is keeping the processor and RAM running at such high levels for so long - both above 80% constantly?

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It shows a list with running processes and the processor load.

Thanks for that, I’ll turn off the antivirus and see if it makes any difference

Thanks! I’ll give that a go!