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A Big Comparison Of The AMD Catalyst, Mesa & Gallium3D Drive
the problem is that there is no sustainable (financially) environment for foss drivers developers outside the HW companies. (its been stated numerous times here by developers that bounties/donations don't work.)
the problem is that there is no sustainable (financially) environment for foss drivers developers outside the HW companies. (its been stated numerous times here by developers that bounties/donations don't work.)
and i don't see this changing in the future
Yeah, which is the reason I believe the Linux driver model isn't up to par with proprietary operating systems. Binary blobs on Linux need to replace big chunks of X.Org to work properly and the kernel interface sucks.
There's also a "conspiracy theory" around this, saying that this is intended by the developers so that big Linux users pay for support from the likes of Red Hat and such.
again no color tiling or pageflipping enabled...
using git but not using the most important performance improvements
Enabling color tiling and pageflipping, and disabling compiz would at least double the open source results.
Oh well...
Still, the interesting thing about the results is that the driver is heavily CPU-bound, which means once these bottlenecks are found and fixed, the performance should increase rapidly.
All r600 and r700 GPUs have basically the same performance, although some of them are 5x faster than others.
Check out the radeon feature matrix - all drivers, all incomplete, all missing the vast majority of 3D related features. Missing as in "To do" - nobody is even working on it. Now that is what I call AMD support.
No, actually, they support the vast majority of 3d related features, and are missing a minority.
The main problem with the open drivers (other than GL3+ support) is performance.
the problem is that there is no sustainable (financially) environment for foss drivers developers outside the HW companies. (its been stated numerous times here by developers that bounties/donations don't work.)
and i don't see this changing in the future
Basic income could be a solution to this problem...
Some games need SM3.0 and that's only avaiable with OpenGL3 or higher...
Not true, SM3.0 is a strict subset of GLSL1.2 with ARB_shader_texture_lod, both of which can be supported by a GL1 driver.
Based on my findings, the low performance can be attributed to these facts:
- We don't use hardware to its full potential (e.g. HyperZ is either not implemented (r600g) or not enabled by default (r300g)). Page flipping is about to emerge in the next kernel. Tiling is not implemented in r600g to my knowledge (and according to the feature matrix). I don't think this point matters much, because the CPU is what limits performance the most.
- There is a command stream checker in the kernel which gives away a little of speed in exchange for security. I'd personally like to see that dropped, but Linus wouldn't accept it.
- The Mesa state tracker and Mesa core slow things down. Some state tracker optimizations are being worked on and that should make the performance a little better. The whole thing could be made faster if the classic driver interface was dropped and both the core and the state tracker were merged together and simplified. This won't happen until Intel jump over to Gallium. Intel are still doing the majority of work on Mesa, so we can't just ignore them.
- Uploading user buffers (like vertices not being in VBOs) is embarrassingly slow. If you wonder why Lightsmark is such a huge failure with open source drivers, then this is the reason.
Ranting about missing GL3 without mentioning WHY GL3 cannot be supported gets old. There are patent issues preventing us from implementing GL3 fully, so it's out of the question now.
It would be very useful if we had comparisons like this article every month or more often, so that we don't live in illusions.
Things haven?t changed much in the last 4 years, performance wise. Gallium3D only boosted performance a bit in certain cases. Knowing about the situation with the open drivers, I don?t really understand why all the complaints about performance. What has changed in the last 3-4 years is the amount of support from the driver. It?s simply amazing how far it has come and this is what really should be praised above all else.
- The Mesa state tracker and Mesa core slow things down. Some state tracker optimizations are being worked on and that should make the performance a little better. The whole thing could be made faster if the classic driver interface was dropped and both the core and the state tracker were merged together and simplified. This won't happen until Intel jump over to Gallium. Intel are still doing the majority of work on Mesa, so we can't just ignore them.
marek since you are a dev and probably know more on the subject do you see Intel dropping classic and going Gallium and if when whats the timeframe.
i remember reading that they were not keen on making the jump
It would make sense to run a window manager which switches compositing off for full-screen apps.
It's 2011, after all. If compiz can't cut it, use something more sane.
No, that won't cut it. Compiz *can* do what you suggest, but this 'feature' is extremely userunfriendly and is thankfully disabled by default. If you disable compositing for fullscreen windows and a notification pops up, you are in for a flicker-fest.
This is 2011 after all, even IGPs have more than enough horsepower to compose a 2 or 3MP desktop.
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