We're glad you are enjoying the preview release! UT2004 has been a favorite on the Raptor side for some time and we are honored to be able to officially enable it on the OpenPOWER platform.
Regarding performance, if you look at the CPU usage while the game is running you will likely see we are not CPU bound in the game itself. This is likely one of the most graphics intensive applications currently available for the OpenPOWER platform, and we suspect we're inadvertently highlighting performance issues in MESA and the Linux kernel on the POWER9 platform. If there is interest in tracking those down in the respective open source components the help would be appreciated -- in fact, anyone that wants to assist in that area can Email Tim directly for better collaboration on the open source side of the stack. It's unclear if we're hitting a GPU bandwidth issue, copying buffers somewhere that we don't need to (MESA/kernel), or if something else entirely is just not optimized for the instruction set.
That all said, the FPS observed is generally within a small percentage of that seen on at least older amd64 systems at similar clocks, so the problem may be more endemic to Linux than the OpenPOWER architecture itself.
