Virtual machine gaming

Where for art thou shaders?
Despite the promises of Direct3D 8.1 compliance, we don’t seem to have any Shader Model 2.0 paths in the benchmarks we’ve tested. This isn’t to say that they don’t exist, but it does suggest that there is more to GPU virtualisation than simply telling the virtual machine to use acceleration capabilities and then letting it ‘figure out’ what paths are available to it. The next step is to try out some games.

Official titles that work
Both Parallels and VMWare have published a set of guidelines stating what games will work with their experimental 3D accelerated virtual environments.

VMWare Fusion/VMWare Workstation
Aliens vs Predator Demo
Breath of Fire IV
Grand Theft Auto III
Hitman 2
Lord of the Realms III
Max Payne 1
Max Payne 2
Need for Speed Porsche Demo
RalliSport Challenge
Tony Hawk 3
X2 Rolling Demo

Parallels
Alien Arena 2007
Baldur’s Gate 2
Bus Driver
Call of Duty
Doom 3
Duke Nukem Manhattan Project
Dungeon Siege 2
GORE – Ultimate Soldier
Hitman Codename 47
Hitman Silent Assassin
Hitman Contracts
Max Payne 1
Max Payne 2
Neverball
Prey
Revolt
Quake 1
Quake 2
Quake 3 Arena
Return to Castle Wolfenstein
Serious Sam – The First Encounter
Serious Sam – The Second Encounter
SiN
Unreal Tournament 2004
Warcraft 3
Wolfenstein – Enemy Territories
Worms 3D

We thought we’d try and bite off a little more than the virtual machine could theoretically chew by trying some very high-end current titles first.

Supreme Commander
Running this game has proven not so supreme. In all virtual machines, the game installs correctly but fails to initialise, not detecting appropriate hardware support. The minimum required system specification suggests we were thinking wishfully (Direct3D 9 and Shader Model 2.0 required).

Half-Life 2
We had high hopes for Half-Life 2, given it is the promoted material approved to work with Parallels. Unfortunately, within Windows Vista, it failed to launch under Parallels. It also failed to launch under VMware Fusion, failing spectacularly and resulting in a BSOD within the virtual machine.



After hours of experimentation, we found the only working solution currently is to use a Parallels v3 build 4560 install with Windows XP virtualised. Finally, we have Half-Life 2 virtualised! Implicit in this is Counter-Strike: Source. Frame rates were gauged with the CS: Source video stress test. Unfortunately, with an average frame rate of between 6 and 11fps @ 1440 x 900, it is hard to consider it playable. A good tweak is to minimise host OS system activity by killing as many non-critical processes as possible, as well as allocating as much homologous system RAM as possible to the VM. Even so, the performance gains are (currently) small.



Quake 4
With a little tweaking on the graphics buffer in the VM configuration (we have found 32MB seems to be optimal for Quake 4), this game runs and runs playable! Shaders seem intact and the levels have all the typical characteristics of a Carmack-crafted creation. Bump maps, normal maps, and specular shading – it’s all there! We maintained an average of 22fps inside levels and around 18fps outside. This was running at 1024 x 768 with no graphical tweaks apart from gamma/alpha adjustment. Typical CPU usage on a Core 2 Duo-based Mac fell between 37 and 54% while in-game, somewhat proving that the GPU was central to the processing work.

Time for something a little different. We decided to try out GTA: Vice City. Note that we found it impossible to run inside Parallels, so in this situation we’ve resorted to VMWare Fusion. Below shows the game running in 1024 x 768, in 32-bit colour. We found serious sound and graphical problems at first. After a little experimentation, we found that the ‘graphical trails/shadow tails’ options needed to be forced off and the sound driver should be turned to D3D Software Emulation. It would not run in hardware/EAX. We recommend refraining from trying to virtualise sound processors while virtualising graphics processors at this stage.



Worth noting is the vmware-vmx process using 163.9% CPU time. GTA3 was by far the most intensive virtualisation task attempted. It essentially used all the resources of both cores and wrote into virtual memory space, above and beyond that of our virtual caged 1024MB limit.

Conclusion
We’ve learnt an important lesson in the process of this tutorial. Just because a set of shaders is ‘supported’ or ‘implemented’ by the hypervisor, doesn’t necessarily mean they will work or render. It would appear that both the VMWare Fusion and Parallels team are working on a game-by-game basis to make titles work with their hypervisor technologies. While VM gaming is becoming a reality, we feel you’ll still be waiting quite a few months to play your favourite game with any fluidity or consistency of experience. That said, every day we creep closer to perfection.