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Re: nanosleep() for shorted than schedule slice

On 2017-07-03 07:25, Michael van Elst wrote: (Johnny Billquist) writes:

Having the normal wall clock driven by a tick interrupt has its points.

We usually avoid this and use what hardware timer the platform offers.

Which is the HZ interrupt, unless I'm confused. And that drives the wall clock, with all the additional bells and whistles of clock adjustments to make sure the clock normally is monotonic, and is just the number of seconds since epoch.

It's just that for high resolution timers, ticks are not a good source.
For anything else, they are just fine. So why conflate the two?

Because you don't need two clock interrupts. The regular interrupt is
just another event that happens to be scheduled in a regular interval.

Right. It would mean having two clock interrupts. Need and need. There are lots of things you don't need, but which might make things more convenient.

But, as I said before, I won't object to any implementation. I was just objecting to the argument that tickless was a requirement for getting high precision timers, which it is not.


Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email:             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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