Seriously, this bug is the last really important hindrance for ditching Catalyst and switching to RadeonSI for real
My kids were having trouble with constant lock-ups of the complete computer when playing under Ubuntu 14.04 with Catalyst - requiring a hard reset. Also I bought the fabulous Goat Simulator which has just been released on Steam, but that had ugly artefacts and blinking. Last night I tried updating to Catalyst 14.6 - but that didn't really solve any issues. (*Crap*)
Then I tried going back to the RadeonSI, but e.g. Kerbal Space Program was running like a slide show. After updating with Oibaf's PPA everything seems to be running really smooth now - except Goat Simulator, which barfs with the LLVM register allocation bug. Boot sequence and switching in/out of fullscreen games is much smoother now. No total system freezes yet.
Quick rundown of Ubuntu 14.04 with Oibafs PPA per 2014-06-28. (Intel i5-3570K with AMD HD7750)
- Kerbel Space Program Demo - Works fine!
- Portal 2 - Works fine!
- Goat Simulator - Crashes with the LLVM register allocation bug
- Trine 2 - Works fine!
- Antichamber - Works fine!
- Minecraft - Works fine!
- Warthunder (under Wine) - Works sort of OK (Similar to Catalyst)
I really, really hope they manage to wrap it up before Ubuntu 14.10
But mesa must be compiled against that llvm 3.5 version, because oibaf ppa mesa packages currently use 3.4 version.
Last edited by dungeon; 07-01-2014 at 06:55 PM.
1.) because the command streaming process is serialised not parallel(may have changed not 100% sure)
2.) because this days the CPU mostly upload stuff to the GPU and then the GPU takes over except shader compilation and other minors details, so if the application doesn't constantly upload data specially shaders and textures (big engines do this a lot) the CPU hit over FPS should be minimal as long as the bandwidth is enough
so, if you wanna have noticeable changes in 3D apps, i believe the first place to look is the command stream dispatcher in the drivers, every optimisation there should improve FPS or load times at least.
another interesting places to look is on the allocation and BOs side in the driver's DRM, track software fallbacks inside mesa, compiler side optimisations(every unnecessary ASM instruction kill a lot of bandwidth and performance due the iterative nature of graphics)
nice for the OpenAL changes