datetime review part 2

Steven Schveighoffer schveiguy at yahoo.com
Fri Nov 26 06:14:53 PST 2010


Jonathan M Davis Wrote:

> On Friday 26 November 2010 04:38:47 Michel Fortin wrote:

> > One thing I wonder about... what is the expected behaviour if you put
> > the computer to sleep in the middle of the above program? With
> > mach_absolute_time, the clock stops counting while the computer is put
> > to sleep. Does TickDuration.currSystemTick works like that on all
> > systems? If there's a difference in behaviour perhaps it should be
> > documented.
> 
> Really? That is... not good. Unacceptable in fact. Even if it were acceptable 
> when dealing with stop watch and benchmarking code (which is questionable), it 
> totally fries Clock.currAppTick(), which tells you how long the application has 
> been running. The documentation for QueryPermanceCounter() and clock_gettime() 
> give no indication that the clock stops counting when a thread is sleeping.
> 
> Do you know if there's another way to get a monotonic clock on the Mac - one 
> which isn't affected by sleep? Much as I'd hate to do it, it would be better to 
> use gettimeofday() and forgo the monotonic clock then have a monotonic clock 
> which is affected by sleep. But I'd _really_ like to have a monotonic clock if I 
> can.

You may have misunderstood. It's when the *computer* is put to sleep, not the thread. It's still an issue, but not as bad I think.

-Steve


More information about the Digitalmars-d mailing list