Loop count and execution time in jmeter

Question

What if I entered: No. of user:100 Ramp up :100 Loop count:30 duration:180sec

Now my question is. 1)How to identify the execution time of thread because i want to know the concurrent user at same time,and its depends upon the execution time of previous user which is might be completed or in process. 2.)And if loop count is 30 then suppose first user comes,it will first hit the server 30 times and then second user arrives?or altogether that first user doesn't hits 30 times an next user arrives even first user not executed fully. 3)I want to check on 100 concurrent user but loop counti have given 30 so concurrent user in the result came to be 21 only.what loop count should i entered so that 100 will become active becuase if i do loop count to be forever,then all the threads becomes active otherwise when loop countis 30,then only 21 is active.Please suggest.

Answer 1

1) Execution Time of a thread depends on your script.

2) The time at which the second user begins depends on your ramp-up, not when the first user finishes. If you have a small ramp-up, your second (or even third or hundredth) user can start before your first user can finish one iteration.

3) I suspect that this has to do with your Thread Execution Time. If 1 user finishes in 3 seconds, it will finish its 30 loops in 90 seconds: which is sooner than your ramp-up. Essentially, the first user finishes before all of the other users start.

I suggest you start with 1 user. Make sure that it executes the way you want it to (pausing to think when a normal user would, etc). If you're using a Duration, you probably want to select Forever. This will mean that your first user will keep executing as all of your threads start.

Without knowing the application you're testing, I can't tell you how to write your tests, but 3 minutes of test (180 seconds) seems very short to me.