jmeter ultimate thread group with relation to constant timer

Question

1. Scenario : a. Ultimate Thread Group : Thread count :100, Startup time : 60, Hold load : 300 b. If there are 10 Http(s) request in the script and each is having 1 sec of constant timer, total constant time value = 10 seconds. In the above scenario the hold time will become 300 +(100 *10) OR 300 +(10) OR 300 -(100 *10) OR 300 -(10)

Answer 1

Your timers on samplers don't have anything to do with your total test time. So in your above example, it will simply be 60+300 seconds.

When a thread finishes its 10 requests, it will start again. So once your test is ramped up, each thread will execute them 30 times. If you increased your timers, the 10 request would take longer to complete, so fewer iterations of them would be done- but it wouldn't change your duration.

Answer 2

Timers and holdtime works independently, they are not related.

In your example-

Test will start loading Threads as test begins and by end of 60 seconds all 100 threads would be up.

Individual thread execution depends on response of each request sent on server (in your case 10 requests/thread), so constant timer will wait for 1 seconds before sending next request of same thread to server.

So, hold time ensures same 100 users(threads) load on server for specified period. As and when one thread completes its execution cycles (all 10 requests), it will add another thread to maintain same load during test time specified as hold time.

Test will get completed in 30+60 = 90 seconds.