On Thu, 26 Oct 2023 16:08:02 +0200 Morten Brørup <m...@smartsharesystems.com> wrote:
> > > In our recent tests, nanosleep() itself took around 50 us. So you need to > > > > > sleep longer than that for your thread not to be runnable when the > > nanosleep() > > wakes up again, because 50 us has already passed in "nanosleep overhead". > > > 10 milliseconds provides plenty of margin, and corresponds to 10 jiffies > > > on > > a 1000 Hz kernel. (I don't know if it makes any difference for the kernel > > scheduler if the timer crosses a jiffy border or not.) > > > > 10 ms looks like an eternity. > > Agree. It is only for functional testing, not for production! To be safe the sleep has to be longer than the system clock tick. Most systems are built today with HZ=250 but really should be using HZ=1000 on modern CPU's.
