Am 21.05.2014 09:31, schrieb Noel Grandin:
> On 2014-05-20 21:11, Karsten Blees wrote:
>>   * implement Mac OSX version using mach_absolute_time
> Note that unlike the Windows and Linux APIs, mach_absolute_time does not do 
> correction for frequency-scaling

I don't have a MAC so I can't test any of this, but supposedly 
mach_timebase_info() returns the frequency of mach_absolute_time(), so you 
could do similar frequency-scaling as I do for Windows with 

> and cross-CPU synchronization with the TSC.

The TSC is synchronized across cores and sockets on modern x86 hardware [1] (at 
least since Intel Nehalem, i.e. all Core i[357] processors). On older machines, 
I would expect the OS API to choose a more appropriate time source, e.g. the 
HPET. I'm not proposing to use asm("rdtsc") or anything like that...


To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to
More majordomo info at

Reply via email to