I want to know how much difference can 2D acceleration in VirtualBox bring ? I only run graphical interface on Windows VMs.
Virtual Box has a still experimental feature to use 2D video acceleration of your host graphic card in a Windows (only!) guest.
This means that you'd expect a performance benefit for video applications in a virtual Windows only. This however is not the typical use case for a virtual machine, as we do have quite mature video playback software natively supported from Ubuntu.
I am using 2DBench to have some numbers about 2D performance: http://www.tomshardware.de/download/Tom2D,1601-26150.html I have run the test three times:
What I have noticed is that my host cpu usage was smaller. So the vm was using my host gpu for some action to lower the cpu usage.
So basically it "brings" you more host performance because not every single 2D action is emulated through the CPU.