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AMD Catalyst Linux Driver Performs Wildly Different Based On Program's Name
An anonymous reader writes: In past years the AMD Catalyst Linux driver has yielded better performance if naming the executable "doom3.x86" or "compiz" (among other choices), but these days this application profile concept is made more absurd with more games coming to Linux but AMD not maintaining well their Linux application profile database. The latest example is by getting ~40% better performance by renaming Counter-Strike: Global Offensive on Linux. If renaming the "csgo_linux" binary to "hl2_linux" for Half-Life 2 within Steam, the frame-rates suddenly increase across the board, this is with the latest Catalyst 15.7 Linux driver while CS:GO has been on Linux for nearly one year. Should driver developers re-evaluate their optimization practices for Linux?
Speed increases may be sacrificing some reliability or cutting some corners. In a FPS game it may be worth it to reduce number of bits in the graphics to increase the frame rate in fast moving images but if you work on photo editing then you want precision rather than speed.
Maybe looking at the name of the executable was an easy way around that.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
Should driver developers re-evaluate their optimization practices for Linux?
Not necessarily. For example, replacing game shaders with optimized platform-specific ones can offer great performance increase with no tradeoffs. The GPU makers know their chip architecture inside out, but game developers usually target a higher level concept such as some shader language. Unless you develop for fixed hardware such as consoles, of course.
There's really two ways how you can relate to these kind of optimizations: "Hey, you're cheating!" or "Cool, thanks for help!". I personally are fine with them, but I would like to clearly know when specific optimizations are in use, and can turn them off when needed. Maybe after application startup the driver could render some popup in the frame buffer such as "AMD Catalyst(R) optimizations in use" which would fade out after a few seconds.
HL2 and CS:GO are meant for different DX versions.
HL2 being originally DX 8.1 and CS:GO being DX9.
Switch to HL2.exe = DX8.1 mode, nuts insane framerate increase.
Rendering capabilities are pre-set by application name in the drivers.
There's your answer.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Probably not directly. To the degree that Microsoft has any specific plan to limit game adoption on non-Windows platforms it is called 'DirectX'. It is the first-class set of APIs on Windows and any games developed for it, or drivers developed to support it, are obviously resources dedicated to gaming being better on Windows and either unavailable or produced at additional cost for OpenGL elsewhere.
Once you get into how AMD's OpenGL driver does(or doesn't) apply application specific optimizations for different OpenGL games, though, MS doesn't have nearly as much to gain from any specific meddling. The general success of DirectX and Windows gaming is presumably the reason why AMD cares relatively little(along with the fact that people looking to use proprietary drivers on Linux usually go Nvidia, while AMD is regarded as very much the second choice unless you are looking for the vendor more cooperative with FOSS driver development).
I didn't notice any visible difference, or rendering errors.
Then again, our renderer is pretty ancient technology by many standards, although in some aspects at par with Doom3 / Source engine. All of these are based on the same-ish code (Quake1) originally and in many aspects OpenGL stuff is very similiar in all three, so I'm not surprised that optimizations carry over. I would expect Xonotic to get some boost too :)