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/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
