jmeter-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Amir Nashat" <anas...@CJ.COM>
Subject Re: Timer Question
Date Tue, 03 Sep 2002 23:16:23 GMT
Mike,

Thank you for your response. It was very helpful. I plugged away some values and played with
the UI and seem to have a better understanding of how the timers work.

I have come along a couple of more questions in which I was wondering if you could help out.
They are:

1) Assume you have 2 threads ( or samples as you call them) and you are using a UniformRandomTimer.
The random delay in milliseconds is 1000 and the constant delay is 5000 milliseconds. Now
the UniformRandomTimer service takes these two values and spits out a delay for the first
thread. Does the second thread then also call the UniformRandomTimer service and get its own
delay as well or is the first delay that was calculated used for both threads? I am assuming
each thread calls the UniformRandomTimer service uniquely and generates its own delay using
the random delay and constant delay mentioned above.

2) In looking through the source code for UniformRandomTimer and GaussianRandomTimer they
both use methods from the Random class. Looking through the Random API I can't really differentiate
how nextDouble and nextGaussian really generate different results. Thus, I can't see the difference
between the Uniform and Gaussian Timer services. Basically, if you use the same values for
the random delay(let's say 1000 ms) and constant delay(say 5000 ms) for the Uniform timer
as for the deviation(again 1000 ms) and constant delay (again 5000 ms) how would the results
differ?

Sorry if I have made this a bigger mess then I probably need to but I would like to get a
clear understanding of the delay that these services provide in order to simulate a real world
environment.

amir



>>> mstover1@apache.org 1:55:57 PM 09/03/02 >>>
Constant timer creates a delay between each sample that is the same for all 
samples.

Gaussian random creates a delay that will average X milliseconds, but in such a 
way as to create a bell-shaped distribution around that average.  The average is 
the sum of the offset (minimum delay) and the deviation (the range of values).

Uniform random timer creates a uniform distribution around the average.

-Mike

On 3 Sep 2002 at 10:25, Amir Nashat wrote:

> Hello all,
> 
> I asked this on Friday but I have had no response so I will ask again. Can anyone explain
the difference between the timer options? The documentation is pretty sparse. Any examples
of which to use in what situation would be helpful. I have researched the faq, help and gone
through google but 
not much has been explained. Any help would be appreciated.
> 
> 
> TIA
> amir
> 
> 
> 
> 
> --
> To unsubscribe, e-mail:   <mailto:jmeter-user-unsubscribe@jakarta.apache.org>
> For additional commands, e-mail: <mailto:jmeter-user-help@jakarta.apache.org>
> 



--
Michael Stover
mstover1@apache.org 
Yahoo IM: mstover_ya
ICQ: 152975688

--
To unsubscribe, e-mail:   <mailto:jmeter-user-unsubscribe@jakarta.apache.org>
For additional commands, e-mail: <mailto:jmeter-user-help@jakarta.apache.org>



--
To unsubscribe, e-mail:   <mailto:jmeter-user-unsubscribe@jakarta.apache.org>
For additional commands, e-mail: <mailto:jmeter-user-help@jakarta.apache.org>


Mime
View raw message