On Tue, 2007-06-26 at 16:58 +0200, Ingo Molnar wrote: > * Mark Lord <[EMAIL PROTECTED]> wrote: > > > Ingo Molnar wrote: > > >Subject: [patch] sys_time() speedup > > >From: Ingo Molnar <[EMAIL PROTECTED]> > > > > > >improve performance of sys_time(). sys_time() returns time in seconds, > > >but it does so by calling do_gettimeofday() and then returning the > > >tv_sec portion of the GTOD time. But the data structure "xtime", which > > >is updated by every timer/scheduler tick, already offers HZ granularity > > >time. > > > > How well synchronized is xtime with real-time ? > > it's updated by every jiffy.
Well, NTP_INTERVAL_LENGTH to be specific which is every jiffie with one exception: With dynticks this is a bit more complicated, and xtime is updated only twice a second. thanks -john - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
