I just installed Loki over my Freya VM that I've been using for the last year and was surprised by the performance difference. It's barely usable.
Cursor hover, clicks, and keyboard input take up to a second to register. Video output in response to user events happens at similar framerates (such as changing the background, instead of a fade, it's a few choppy frames).
Fresh install with plenty of CPU and memory on the host and the exact same VM configuration and host I used for Freya.
I suspect the problem is actually with the video output rather than the actual input, and processes in the background seem to run at full speed.
- macOS 10.11.6
- 16GB RAM
- 3Ghz i7 Dual-Core
- VirtualBox 5.0.26 w/ Extension Pack
- 2GB RAM
- I/O APIC, PAX/NX, Nested Paging
- 1 CPU, no Execution Cap
- 128MB Video Memory, 3D Acceleration, Scaled HiDPI (low res)
- USB 3.0 xHCI Controller (also tried with USB 2.0 EHCI Controller)
- Guest Utils Installed from VirtualBox virtual CD-ROM Image (DKMS, linux-kernel-headers-generic, build-essential packages installed via apt)
- Disabled 3D Acceleration in Virtualbox - noticed massive improvement in responsiveness, confirming(?) my suspicion that the problem lies in the video rendering and not from input lag.
So the real question is why does Loki's 3D VM Accelerated performance suffer so hard in comparison to Freya's?