Since ı bought my PC around a year ago, it has had a near constant 100% disk usage in task Manager, and has been relatively sluggish. After some research ı disable telemetry (windows reporting service) and my disk usage is down to around 3%. This is Very cool for me.
If you want to disable it, run regedit,
hkey_local_machıne > software > policies > Microsoft > Windows > datacollection. then create a New 32 Bit d-word Value, name it "allow telemetry", and set value-data to 0. should be all done. Hope this helps.
How I fixed constant 100% disk usage : Windows10 (reddit.com)