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Re: [ns] random variables Vs simulation time



Do you have many upcalls to tcl?

Tarik Alj <[email protected]> writes:

> Yes, I was using uniform random variables with the min_ and max_ set to coherent 
> values. Plus I was getting the "scheduler going backward in time" message. I was 
> using scheduler.cc v1.42, after I changed to scheduler.cc v1.46 the problem 
> disappeared but the simulation kept taking forever to complete.
> 
> > 
> > Did you check your random packet size? Some ranvars may generate huge
> > packets. Just a guess.
> > 
> > - Haobo
> > 
> > On Thu, 16 Mar 2000, Tarik Alj wrote:
> > 
> > > Hi everybody,
> > > 
> > > 	in my scripts I have been using a proc that uses 2 random variables to 
> > > set random packet sizes and rate for cbr sources. About 20 CBR sources are 
> > > generated like this, the topology is fairly small (5 nodes), and the 
> simulation 
> > > time is 3000 seconds.
> > > 	It takes about 2 hours to complete, Vs a few minutes without using 
> > > random variables. Has anybody experienced the same kind of behaviour? Does 
> it 
> > > have anything to do with the scheduler? 
> > > 	
> > > 	Answers, suggestions, pointers would be greatly appreciated.
> > > 	
> > > 	Thanks,
> > > 
> > > 
> > > Tarik
> > > 
> > > 
> > > 
> 
> Tarik