When I started Linux I was confused by the cpu/processor scheduler and IO scheduler, would be even better if the article can point out the difference briefly.
In AI workload these days, how to schedule thousands of parallel threads(SIMD style) becomes more and more interesting, wish someone had a good write on that topic.
CPU Shaders have a very simple scheduler. Blocks are scheduled one block at a time likely in some very simple heuristic (likely from lowest index to highest index, though nominally you don't know what order they're executed in).
That's good enough in 90% of cases. The last 10% can be served by a variety of techniques, including long-running kernels, data-structure queues, dynamic parallelism, etc. etc. But mastering the basic kernel invocation in the classic "matrix multiplication" scenario (roughly lining up with OpenMP "static scheduling"), and its benefits, is a good idea.
Lots of cool papers to read.
At least that's the theory. I think these days the kernel reserves (optionally?) 5% cpu to non rt tasks, enough to run a shell and kill a runaway rt process.
That is the default setting (documentation [0]).
