its only prefetch which will activate more threads. if you have set the prefetch amount to very little it might be able to grab that in a single thread.
i prefetch 400 mb (20x20mb) at 160 sec timeout. It will start by getting with 20 threads and then 1-2 as it grabs while you read
Pinned data is data about folders etc. to make your browsing better. Cached data is partial data located on your drive to help speed up load times - this value can be changed at any point to none or a lot more.
Left pie chart shows data on your drive and what parts is what. Mostly this chart will be dominated by "to upload" when you have copied data to your drive.
Right side shows how much if your data is located locally vs in the cloud.
You can resize your drive in the drive options located under the left pie chart.
