Gallium3D LLVMpipe Starts To Smoke

[phoronix]

Phoronix: Gallium3D LLVMpipe Starts To Smoke

While it's rare for a few days to pass at Phoronix without pulling the latest development code for Mesa / Gallium3D and the Linux kernel DRM in order to run updated Radeon, Intel, and Nouveau Linux graphics benchmarks, LLVMpipe isn't benchmarked as commonly. LLVMpipe is the new CPU-based software acceleration method for the Gallium3D that leverages the Low-Level Virtual Machine to provide better performance than the classic Mesa software rasterizer or Softpipe. Fortunately, upon running a brand new set of tests, the results show a bit more promise but there is still much work ahead.

http://www.phoronix.com/vr.php?view=16453

[pingufunkybeat]

It's nice to see the state of llvmpipe, and it's very impressive for a purely software renderer. But how on Earth did you manage to get 20 fps with HD 5450 in OpenArena?

I get close to 60fps in 1080p with an HD 4550 (which is about equal in terms of performance), and this has been the case for about a year. 25fps at 1024x768 is something I can't achieve even with low power profile and anti-performance tweaks.

Since all tests but one are capped at exactly 60 fps, I'm guessing it's the vsync issue again.

[FireBurn]

It would be interesting to test this on the 6core i7 again and compare against the last test to see the improvements

[Creak]

Why comparing LLVMpipe (which is a software pipe) to RadeonHD and Nouveau (which are hardware accelerated pipes) ?
Why not comparing LLVMpipe to Mesa, to see the real improvements between the two solutions?

These are real questions, I might have misunderstood some subtlety about the rendering pipe...

[Creak]

It would be interesting to test this on the 6core i7 again and compare against the last test to see the improvements

+1
Compare Mesa and LLVMpipe with CPU with more and more cores, to see if LLVM handles it better than GCC. (but I make a lot of assumptions here, correct me if I'm wrong)

[FireBurn]

Why comparing LLVMpipe (which is a software pipe) to RadeonHD and Nouveau (which are hardware accelerated pipes) ?
Why not comparing LLVMpipe to Mesa, to see the real improvements between the two solutions?

These are real questions, I might have misunderstood some subtlety about the rendering pipe...

I agree, dedicated hardware should always win

[Veerappan]

I agree, dedicated hardware should always win

That first OpenArena test looks a bit suspicious to me. Not in the testing methodology, but that we may have an opportunity to identify a CPU bottleneck in the Gallium/LLVM/Radeon architecture.

One of these days I'm hoping to starting profiling the r600 driver to see if there's any way I can help. Otherwise, I'll probably start working on fleshing out the GSoC clover implementation a bit (implementing built-in math functions and stuff, conformance testing, etc).

[Creak]

BTW... I'd like to buy a new graphic card, is it good to take an ATI now? I prefer their "open" policy, but I don't know if the open source driver is good enough.
For instance, I have an nVidia card at the moment and if I use Nouveau, the temperature gets higher and higher, way above 100°C.
It took me some time to understand why my PC was freezing without any reason...

Since RadeonHD drivers are based on open specs and aren't retro-engineered, are they more stable?

I don't play huge games on my Linux, but I do 3D programming.

[Creak]

One of these days I'm hoping to starting profiling the r600 driver to see if there's any way I can help

I'd be glad to help you in this as soon as I've got an ATI card (see previous message).

[aaaantoine]

I continue to wonder if this will ever breathe any life into the non-T&L Radeon Xpress 1100/200M

I suppose the desired behavior would be to fall back to LLVMPipe instead of the current soft pipe for operations not supported by the GPU.