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Re: Going back in time?
Hi,
That works .. i was able to find the culprit.
But i was wondering if the only solution is to reduce the
traffic generated by that source (in my case Link Layer).
Is there any other solution ?
Deepesh
On Tue, 27 Jul 1999, Massimo Pegorer - stage wrote:
> Have you modified anything in NS code?
> I've had this problem becouse of incorrect calls to Scheduler::schedule.
> If something schedule an event with a time already gone (minus than
> current time of the scheduler), the Scheduler::dispatch will generate
> that message.
> I've solved my problems debugging with a breakpoint in scheduler.cc line
> 99 ( fprintf(stderr, "ns: scheduler going backwards in time from %f to
> %f.\n", clock_, t); ), and than with backtrace to find the incorrect
> scheduling.
> Hope this helps,
>
> Max
>
> --
> Massimo Pegorer, student
> Dipartimento di Elettronica e Informatica
> Universita' degli Studi di Padova
> Padova - ITALIA
>
> Deepesh Chouhan wrote:
> >
> > hi,
> >
> > But i am sending ARP-like packets along with TCP packets ..
> > so do they also create problems ?
> >
> > Deepesh
> >
> > On Mon, 26 Jul 1999 [email protected] wrote:
> >
> > > hi,
> > > i have seen this thing happen. one of the cases is when you attach
> > > a member of the /Application/Traffic/.. to TCP sources. This is
> > > because TCP has its own scheduling mechanism based on the cwnd and
> > > other parameters and trying to force it to send packets according
> > > to times generated by traffic generators from /Application/Traffic/..
> > > may violate some restrictions.
> > >
> > > the bottomline is this may happen if you are attaching a traffic
> > > generator to TCP sources. hope this helps,
> > >
> > > biplab
> > >
> > >
> > >
> > > On Mon, 26 Jul 1999, Deepesh Chouhan wrote:
> > >
> > > > hi,
> > > > even i got this error ..
> > > >
> > > > Please, can somebody help us out.
> > > >
> > > > Deepesh
> > > >
> > > >
> > > > On Mon, 26 Jul 1999, Daniel Friedman wrote:
> > > >
> > > > > What are some general or specific reasons to diagnose why NS might
> > > > > go backwards in time? As, for example, when the simulator gives a
> > > > > message like this one:
> > > > >
> > > > > ns: scheduler going backwards in time from 324.400754 to 324.349757.
> > > > >
> > > > > Thoughts?
> > > > >
> > > > > Thanks,
> > > > > --daniel
> > > > >
> > > > > ---------------------------------------------------------------------------
> > > > > Daniel Friedman [email protected] http://www.isr.umd.edu/~danielf
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
>