Re:The Linux realtime preemption endgame is near
by josephg on Friday November 17, 2023 @07:49AM
(#38302784)
How did it achieve its speed? My understanding was that microkernel architectures were fundamentally slower than monolithic kernels because context switching is slower than function calls. How did L4 manage to be the fastest?
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Re:The Linux realtime preemption endgame is near
by vacuity on Friday November 17, 2023 @10:00AM
(#38304451)
Two factors are the small working set (fit the code and data in cache) and heavily optimized IPC. The IPC in L4 kernels is "a context switch with benefits": in the best case, the arguments are placed in registers and the context is switched. Under real workloads, microkernels probably will be slower, but not by much.