Mesa 19.2 Picks Up The Radeon R300~R500 Series On-Disk OpenGL Shader Cache

Last week an on-disk GLSL shader cache was proposed for the vintage "R300g" open-source Gallium3D driver for this OpenGL code supporting through the Radeon X1000 (R500) series. That shader cache support has now been merged into Mesa 19.2.

With this shader cache taking advantage of the Gallium3D on-disk shader cache infrastructure introduced a while ago and already utilized by the newer Gallium3D drivers, just a bit of code was required to hook it into this R300g driver that these days is just an after thought. It will be interesting to see how this shader cache manages to help the performance for these vintage ATI graphics cards especially after there was also another important R300g performance fix recently.

The GLSL on-disk shader cache usually helps with speeding up load times and smoothing out frame-rates for any games loading shaders on-demand. No benchmark/test results were provided by the contributor adding this support. I would test the R300g on-disk shader cache with some OpenGL benchmarks using some old R500 graphics cards, but I'm anticipating the results to be a wash. There are not many shader-heavy games that run well on these very old graphics cards so the impact may not be all that different, but we'll see.

But at least the addition adds to the growing list of new features for Mesa 19.2.