Re: Anyone else interested in a high-precision monotonic counter?

["Manfred Bartz" <md-linux-kernel@logi.cc>]

"Christopher Friesen" <cfriesen@nortelnetworks.com> wrote:

> Manfred Bartz wrote:
> 
> > Why a new system call?
> Well, you'd be accessing a different kernel variable--"ytime" instead of
> "xtime". This new variable wouldn't be adjusted when the  system
> time/date was, it would start at zero and always increase. 

> > have you looked at the return-value of times(2)
> > Or roll your own using setitimer(2)
> 
> Both of these are precise only to jiffies, which defaults at 10
> milliseconds on x86 and PPC.  If you want microsecond timing, the only
> current standard way to do it is to use gettimeofday(), which is
> sensitive to changes in system date and time.

Ok.  A monotonic, high resolution timer would be useful.

Maybe one should then push for a full implementation of xtime
including TIME_MONOTONIC and TIME_TAI?

        <http://www.cl.cam.ac.uk/~mgk25/c-time/>
        <http://cr.yp.to/time.html>

-- 
Manfred
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