virtualbox.org

I have Windows 10 host, inside there is windows 10 guest that is supposed to do some computations all the time.
I set the power management so that it does not put the host into standby. The only power management feature that I set is "Screen off after 15 mins".
Apparently, when the screen goes off so everything works, but the guest runs around 5x more slowly than with the screen on.
On the host I tried to set "max performance profile" but it didn't help.

The VM has no control over the CPU speed, so I suggest you look to host settings. Sounds like the clock speed may be reduced.

mpack wrote:The VM has no control over the CPU speed, so I suggest you look to host settings. Sounds like the clock speed may be reduced.

I agree.

I did the following experiment: On host as well as the guest I installed TeamViewer.
When I use TeamViewer to access directly the guest (during this the screen of the host stays off), so I see all its cores are 100% used, but my application runs slowly.
When I use TeamViewer to access the host (in this moment the screen goes on automatically), so I see that the application in the guest displayed on host's desktop runs quickly.

Ok, so the problem is in the host setting, but I have no idea how to make it run on 100%. It is Windows 10 notebook Microsoft Surface Pro 3. I tried to set performance profile on "Maximum performance" but that didn't help. Besides that I am not able to find further settings...

Also, when I was running the application directly on the host, so I didn't have the problem - it was running quickly with the screen off.
So that's why I ask here in the VirtualBox forum - it seems that it is the VirtualBox VM that is not using the full performance of the host with the screen off, while what a single application can do it.