On Wed, 15 Feb 2012 20:56:26 +0100 "Martin v. Löwis" <mar...@v.loewis.de> wrote: > > With the quartz in Victor's machine, a single clock takes 0.3ns, so > three of them make a nanosecond. As the quartz may not be entirely > accurate (and also as the CPU frequency may change) you have to measure > the clock rate against an external time source, but Linux has > implemented algorithms for that. On my system, dmesg shows > > [ 2.236894] Refined TSC clocksource calibration: 2793.000 MHz. > [ 2.236900] Switching to clocksource tsc
But that's still not meaningful. By the time clock_gettime() returns, an unpredictable number of nanoseconds have elapsed, and even more when returning to the Python evaluation loop. So the nanosecond precision is just an illusion, and a float should really be enough to represent durations for any task where Python is suitable as a language. Regards Antoine. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
