On-Disk Shader Cache Revised For Mesa, Close To Landing

Timothy Arceri of Collabora has updated the hardware agnostic portion of the on-disk shader cache patches.

The hardware/driver agnostic portion of the on-disk shader cache patches amount to 37 patches against Mesa Git master. For the uninitiated, this is the long ongoing work about offering an on-disk cache of OpenGL GLSL shaders once compiled by the respective Mesa/Gallium3D driver. This can speed-up subsequent load times of games, improve playability for games that require new shaders to be compiled in-game, etc. Arceri has previously mentioned this Mesa shader cache patch-set has substantially improved the Intel Mesa driver's performance in games like Shadow of Mordor.

With these hardware-agnostic on-disk shader cache patches they are to a stage where he hopes to be able to merge the work soon. Details via this patch series.

Initially this shader cache may be disabled by default, but can be enabled via MESA_GLSL_CACHE_ENABLE=1. Additionally, separate from this patch series, so far there are just the driver-specific portions of this shader cache implemented for the i965 Mesa driver. Thus for now RadeonSI and friends will be without this functionality. GLSL shader caches have been present in the proprietary graphics drivers for years.

As this big patch-set is too late for the Mesa 17.0 merge window, the cache could end up being one of the main features for Mesa 17.1 to be released in Q2.