@limetech please look into this issue. I have a single MX500 SSD BTRFS Encrpyted installed and everything comes to a halt when there are concurrent filestreams handled. The UI shows that the SSD is reading 500mb/s continuously. Average load is 27. This mayor issue is at least two years old.
I have the Mover schedule set to: "hourly"; Time of the day: "Every 4 hours". Additionally I have enabled the Mover logging. As seen in the log files, no files are moved from the cache drive to the array. Only when I invoked the Mover manually, it would work.
tower-diagnostics-20200313-1029.zip