That’s an interesting perspective. I‘m not sure I‘d ever be able to act on this outside of some embedded environments - even there, we now have actual OSs and the variance that comes with them.
Context switches on most general purpose OS's are non-preemptible. It's relatively easy to find out what they cost. The TLB hit is application dependent - it depends on the working set (memory use footprint) after the switch. This is not some hard to know thing, certainly not for the purposes of bounding a spinlock.
