I know this is a very common problem for whonix users but here is my story.
About two weeks ago just over night my tor has become extremely slow and weird, speed around 10-50kb and sometimes even lower, i couldnt even update and upgrade system, connections drop over and over again then i decided to fix it somehow but without any success. My connection is very stable and i never experience any connection drops without using tor, so i fully rebooted my router, tried out various VM settings (different controllers, amount of ram and cpus, and so on), bridges even worsen performance…nothing helped.
After i imported VMs, i followed " Spoof the Initial Virtual Hardware Clock Offset" tutorial and thought this shouldnt be a problem but now when i imported fresh VMs without hardware clock spoofing my tor performance instantly went back to normal.
Do you see any connection between hardware clock spoofing and poor tor performance?