Re: Ktimer / -rt9 (+custom) monotonic_clock going backwards.

[Steven Rostedt]

On Thu, 20 Oct 2005, Steven Rostedt wrote:

>
> On Thu, 20 Oct 2005, Steven Rostedt wrote:
> >
> > FYI, I just merged my changes with -rt13 and everything seems to be
> > working very smoothly.  I've been running my kernel over an hour without
> > showing the backward times. I haven't even added the change from cycle_t
> > to be 64 bits.
> >
> >
> > So, knock on wood, maybe one of the latest updates fixed the problem. Or
> > maybe as soon as I hit send, the machine will crash.
> >
> > I'll keep you all posted.
> >
>
> Spoke too soon ;-)
>
> About ten minutes after sending this, the clock went backwards, and once
> again by 2 seconds.
>
> now=5856:283756196 last_count=5858:436968526
>
> Where now is 5856.283756196 seconds and last count is 5858.436968526.
>

Pádraig sent me an email showing that this time difference is what it
would take a 2GHz machine to overflow a 32 bit number.  I'll go and switch
the cycle_t to 64 bits and see if this solves the problem.

-- Steve


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