On Fri, 08 Jun 2018 16:49:48 -0500, Àbéjídé Àyodélé said:
I have a machine with 80 cores and I had a burst of requesting more cpu period than the available number of CPUs, my guess was that this resulted in starvation for the kernel threads, is my guess plausible or do kernel threads get preference for scheduling.
The short answer: 'man 7 sched' The long answer: The first question is, of course: "Did you see any actual evidence of kernel threads being starved?" In general, CPU-bound execution threads get lower priority than threads that are I/O bound or otherwise bursty in behavior, so kernel threads (which almost never go CPU bound) end up getting scheduled before cpu-bound threads. However, it *is* possible to shoot yourself in the foot by setting artificially high priorities on CPU-bound processes and/or setting processor affinity or fully tickless kernels to end up accidentally starving some kernel threads.