On Mon, Nov 29, 2021 at 11:07:07PM +0100, Thomas Gleixner wrote: > On Fri, Nov 26 2021 at 22:52, Peter Zijlstra wrote: > The size is the same, i.e. 1 bit per nanosecond :) :-) > > The only time that's relevant though is when you're going to mix these > > timestamps with CLOCK_THREAD_CPUTIME_ID, which might just be > > interesting. > > Uuurg. If you want to go towards CLOCK_THREAD_CPUTIME_ID, that's going > to be really nasty. Actually you can sleep on that clock, but that's a > completely different universe. If anything like that is desired then we > need to rewrite that posix CPU timer muck completely with all the bells > and whistels and race conditions attached to it. *Shudder* Oh, I wasn't thinking anything as terrible as that. Sleeping on that clock is fundamentally daft since it doesn't run when thats is sleeping, consider trying to sleep on your own runtime :-) I was only considering combining THREAD_CPUTIME timestamps with the UMCG timestamps to compute how much unmanaged time there was, or other such things. Anyway, lets forget I bought this up and assume that for practical purposes all [ns] are of equal length.
