Let’s face it. Apple has done a terrible job producing reliable drivers for OpenCL and Metal compute shaders. Each Mac OS update brings the terror of: Did Apple kill the drivers this time?
Since March 2017, the state of OpenCL drivers for AMD GPUs has been: Unusable
Either the app crashes or you get a total system lockup with OpenCL AMD rendering. (late 2016 MacBook Pro with AMD GPU)
With about 100 different Mac configurations released in the last 6 years that have GPUs, your results will probably be very different.
For the 5 previous years, the AMD OpenCL drivers had been rock solid.
Fractal Architect is the “Rosetta Stone” for GPU compute testing. It allows you to easily switch render devices between OpenCL, Metal, and CUDA. It allows you to check their LLVM compilers for their ability to compile the extremely complex kernels used by the app.
It allows you to profile and compare performance between devices and between different Mac models.
But supporting GPU rendering is very expensive. Guess who pays for all of the test Macs?
The revenue base to support this GPU support feature is tiny. Flame fractal apps are a micro niche. To date (since 2009) the entire revenue from the app goes toward buying test hardware and nothing else !
This year, because of driver quality problems, worldwide sales of the app are now so low that I can only buy 1 test Mac every 3 years. I cant test the app on a current generation AMD GPU on a low end MacBook Air. I can’t test next years AMD GPU on last year’s Mac.
A) GPU rendering be removed from the app as test hardware is cost prohibitive?
or B) should it be left in because it will probably work with fixed drivers on future GPUs?