Gatling fail when open large number of connections


I am using the websocket library to test a websocket server. When I use around 2000 connections(users), Gating simply freeze. It does not report anything.

Does anyone know how to solve this problem?

Thanks in advance,


I am using 1.5.3 with the third party libray

Everything is in your sentence: third party = not maintained here.

Actually, this was contributed into Gatling and next 2M4 will ship websocket support.

There’s still a few things to tweak, but I was able to run 2.000 concurrent websockets against Play!'s chatroom sample on my local computer.

Thanks for your reply!

Well, here is what happened in our test. After creating 2000 concurrenct connections to our local server. Our server dies, which is fine for us. But the Gatling cannot finish as well, it is freezed somehow. As a testing tool, I assume Gatling is able to handle server failure. However, during our test, it fails when our server fails. Is this a bug in Gatling or did I miss something?

My 2 cents: that’s a bug in this third party.

2 possibilities:

  • you either stick to this third party, but then open an issue there
  • you migrate to latest Gatling 2 snapshot that ships a refactored version of this websocket support, and if you can still reproduce, then I’ll gladly investigate