I was sitting next to my Windows 10 PC using my phone when my computers disk started to go wild. I proceded to move the mouse and the buzzing stopped. Naturally I decided to investigate and opened my task manager, there I monitored the disk usage and made sure to not touch the keyboard or mouse. after approx. 4 minutes of waiting the disk went from 0% usage to 100% usage and stayed there until I moved the mouse again.
What I then noticed was that two processes specifically stood out from the rest. Namely the "System" and the "Service Host: Disk Defragmenter" processes.
My Questions are:
What is happening in this specific situation, is Windows just defragmenting my computer in the background or is this something else?
The first question is really all I need answered for this situation, but just in case the answer isn't what I expect it to be: Is there need to be concerned if this kind of thing happens? As in: Could a virus potentially infiltrate the System process?