note, openCL is different to openGL, mostly being more about more accurate computations. On AMD FX4300, 32bit userspace but llvm probably uses avx? guest@slax:/dev/shm/mesa/BUILD$ RUSTICL_ENABLE=llvmpipe clpeak Platform: rusticl Device: llvmpipe (LLVM 20.1.3, 256 bits) Driver version : 25.2.0-devel (git-845611bb43) (Linux x86) Compute units : 8 Clock frequency : 300 MHz Global memory bandwidth (GBPS) float : 3.72 float2 : 4.08 float4 : 3.59 float8 : 2.81 float16 : 2.09 Single-precision compute (GFLOPS) float : 14.67 float2 : 17.86 float4 : 15.99 float8 : 14.72 float16 : 14.63 No half precision support! Skipped No double precision support! Skipped Integer compute (GIOPS) int : 13.89 int2 : 13.25 int4 : 12.85 int8 : 13.04 int16 : 11.51 Integer compute Fast 24bit (GIOPS) int : 13.65 int2 : 13.29 int4 : 13.23 int8 : 12.90 int16 : 11.08 Transfer bandwidth (GBPS) enqueueWriteBuffer : 2.82 enqueueReadBuffer : 1.08 enqueueWriteBuffer non-blocking : 2.89 enqueueReadBuffer non-blocking : 1.02 enqueueMapBuffer(for read) : 1.15 memcpy from mapped ptr : 3.02 enqueueUnmap(after write) : 2.22 memcpy to mapped ptr : 3.01 Kernel launch latency : 21.55 us guest@slax:/dev/shm/mesa/BUILD$ command to build somewhat minimal mesa (llvmpipe + amd): meson ../ --prefix=/usr/X11R7 --libdir=lib --strip --buildtype debugoptimized -Degl=enabled -Dosmesa=true -Dplatforms=x11 -Dgallium-drivers=r600,radeonsi,llvmpipe -Dvulkan-drivers=amd,swrast -Dgallium-nine=true -Dgallium-va=enabled -Dgallium-xa=disabled -Dgallium-rusticl=true -Dllvm=enabled -Drust_std=2021 -Dvideo-codecs="all" of course you can set your own prefix ( I have X installed into non-default location). Biggest obstacle for me was that mesa git require some new llvm, and just released two days ago SPIRV-Tools-2024.4 ! And github "release" is of course broken, in sense you need to manually fetch headers at specific commit. Of course "real gpu" will get like >200 GFLOPS , even my puny GF710 was that fast, but possibility of lock up makes this option less attractive ;)