[OpenSTA-users] Why isn't my Random variable very random?

[Stephen K. <Ste...@on...>]

I can't quite get the hang of random variables and I'm sure I'm missing
something, but I've looked at the help, sourceforge and tried some tests,
but can't work out what I'm doing wrong.

To highlight the problem I created a tiny script.

I have this line in my definition section of script:

      Integer           userthinktime     (5000 - 20000), RANDOM

Then in the code section of my script I have these lines:

      generate userthinktime
      log userthinktime

If I run this script in the modeler it logs a random value each time and
that's good.  However, when I run this as a test for 10 seconds with 10
users running the same script I get this sort of thing in the logs (i.e. it
increments by a few milliseconds each time):
LOG: 13373,
LOG: 13376,
LOG: 13379,
LOG: 13382,
LOG: 13386,
LOG: 13389,
LOG: 13395,
LOG: 13399,
LOG: 13405,
LOG: 13409,
LOG: 13412,
LOG: 13425,
LOG: 13428,
LOG: 13431,


What I want is a genuinely random variable picked up by each virtual user
running the script, but I can't work out how to do it.  I'll keep trying
but if anyone knows how to do this I'd appreciate a nudge in the right
direction.

Thanks, Steve



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