On Wednesday 13 August 2008, John Kasunich wrote: > Unfortunately, conversion from clocks to time is non-trivial, so we > simply report the results in clocks.
(get_cycles()*10^6)/cpu_khz Is that non-trivial ?? > The situation is getting worse, not better. In the name of "progress", we > now have to deal with CPUs that change their clock frequencies on the > fly. You need to read the RTAI docs again - Disabling CPU_FREQ is *strongly* recommended because it messes up realtime response. But if you have disabled all power management, that option will not be available. > I've even heard a report that on some modern CPUs, the TSC can no longer > even be counted on to be monotonic. Almost correct - What happens with multiple processors is the TSC drifts slightly, however, recent developments in the kernel & RT patches periodically resyncronise the TSCs. Disregarding TSC drift, the value returned will be accurate enough for your needs. --- Paul. ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
