virtualbox.org

Why are there huge VM performance differences with the same guest OS on different host OS's?

The best example is Netflix streaming. It is absolutely unwatchable when I try to use it through my Windows XP guest on an Ubuntu 10.04 host. Video skips and the audio stutters.

How is that possible?

Netflix streaming works fine on a Windows XP guest, as long as I use a Windows 7 host.

In all cases, I am running Virtualbox 4.0.4, and I have the 4.0.4 Guest Additions installed to the guest OS. Both VMs are set up with 128 MB video RAM, 2D and 3D acceleration enabled, 1 GB of system RAM assigned. So the only difference is the host OS. I don't get it.

Eventhough guests run virtualized they still use indirectly resources from the host, so it also depends how well a host deals with the real hardware including bugfree video drivers/gui.

If that's the case, the Nvidia Linux drivers must be absolute crap.

Rendering a 2D video stream at roughly DVD quality is not something that should challenge today's hardware.

update:

Looks like this is fixed! I just upgraded to the latest Linux Nvidia drivers (260.19.44), and now Silverlight plays smoothly on my virtual Windows XP machine.

It's still a little wonky. For example, if I put the XP machine in "Fullscreen" mode while the Silverlight content is already playing, the VM promptly crashes. But I'll take what I can get.

With nvidia its a different case, they keep 3 release platforms, 1 for os venders (MS), 1 for common flow and 1 for the CAD world, its best to use google with a release version to check if the 'beta' works for others.

"CAD world?" You must be thinking of the Quadro drivers. Why would I want those?

And beta drivers? Again, I don't understand what you're getting at.

FWIW, my small triumph was short-lived. Ubuntu 10.04 has a long-standing inability to deal with current Nvidia drivers. Manually install newest Nvidia drivers = GUI crash on next boot. I had to go back to the 195.something Linux drivers.

I don't have issues with nvida and Ubuntu. Never have.
I even run the latest and greatest from the PPA.
http://ppa.launchpad.net/nvidia-vdpau/ppa/ubuntu
As for playing a stream in the guest, something that I am sure you have realized is you are really using the hosts RAM for memory instead of the GPU memory. I find that tweaking this helps some. 128MB is not always the best for the guest, One of my guests works at 32MB better than => 64MB
Also streaming is CPU intensive on a guest since the 3D/2D is software rendered. It should be a lot better once WDDM is released in VBox.

Perryg wrote:It should be a lot better once WDDM is released in VBox.

When??

Friday

Perryg wrote:I don't have issues with nvida and Ubuntu. Never have.
I even run the latest and greatest from the PPA.
http://ppa.launchpad.net/nvidia-vdpau/ppa/ubuntu

Thanks, that turned out to be the key.

I used the PPA install method (add PPA to source, run apt-update, install from there) and I've been able to reboot with no GUI problems. Now using the 270.29 drivers as well.

What didn't work was, downloading a Linux drivers package from the Nvidia website (e.g. NVIDIA-Linux-x86-260.19.44.run) and attempting to install it at the command line. I would always get some kind of error during the install, then the GUI would pretend to work..until the next time I rebooted, in which case I'd have to choose either console login or low-graphics mode.

update:
Well, so much for that. I keep having random lockups. Didn't have those before installing the 270.29 drivers. Guess that's why they're "beta" drivers.

Is there some way I can roll back to the 260.something drivers?