I just upgraded from Gatling 2.3.0 to 3.2.0 and now for the same job, the same configuration, I have java.lang.OutOfMemoryError: Java heap space errors as soon as I have more than 2 users in parallel. With the previous version I can run more than 150 users at the same time. The only change is the upgrade of version.
You can find the hprof file here : https://drive.google.com/open?id=1eAefbsQmo4WZ131Nd-TjTbCkhcPinTeT
It’s a big scenario, but it works fine with gatling 2.3.0.
It tried to increase Xms and Xmx but it still crashes.