Hi,
So the minimum appears less than what you expect with a high number of threads such as 100? Or are you able to run with a 100 threads again and get the minimum you would expect? It's possible that because of the high number of threads that if all you are doing is sleeping in the scripts that they could finish faster as the sleep method does not guarantee the amount of time the script will be idle. If you are still having the minimum be much lower than you would think with 100 threads or more I can have development take a further look at this. Also, there is a thread cap at 200 threads during a load test. If you would like to increase this amount then you will need to use the -Dsoapui.threadpool.max SoapUI jvm property. See this link for more information
http://www.soapui.org/Load-Testing/threads.html.
Regards,
Marcus
SmartBear Support