Tsung is taking an enormous amout of time to hand of response to plugin.

[sylane]

trafficstars

I wrote a tsung plugin for our custom websocket protocol. Everything seems to work fine, but with time I was seeing the request duration goes inexplicably high. I inspected the protocol with wireshark and the response time was looking fine. I added a timestamp in the response on the server to measure the time between the server was responding and tsung was handling the packet (both server and client are run locally). The result is showing that everything starts fine but after some time Tsung is calling the plugin parse function with a growing inexplicable delay, sometime multiple minutes after the server sent the packet ! Does anybody have an idea of what could be wrong ?

[tisba]

just a wild guess, but was tsung (the controller and/or nodes) be under load? Without more information I don't have any other good ideas currently :-/

[sylane]

The machine load was ~1 (4 core) and there was only ~15 concurrent sessions... The scenario is not doing that much, and the plugin is only doing some JSON parsing. While debugging I can see that the time between set_opts and receiving the next packet takes 10s + while the server responded in 95ms (on the same machine). If the issue is the load it would mean tsung wouldn't support 15 concurrent sessions on a high-end machine, that would be weird.

[nniclausse]

it's weird indeed. Can you give more details on how you are handling websocket in your tsung plugin ?