Gatling hangs at end of test

[Pete_Capra]

Hi there,

I’m having a sporadic issue with Gatling hanging at the end of a test run. I’m executing http requests with 25 users continuously for 10 minutes and at the end of the cycle it just hangs before it starts to generate the report. It seems to be happening about 2 in 3 times. It doesn’t seem to be the same issue as https://groups.google.com/forum/?fromgroups#!topic/gatling/imrKgB0z-54. The only thing the log gives away is the not all scenarios are marked as ended.

Any ideas?

Cheers,

Pete

[Excilys]

Hi Pete,

What version of Gatling do you use?
Did you have any kind of failures logged in the console while running?

Cheers,

Steph

2012/5/4 Pete Capra <petey.caps@gmail.com>

[Pete_Capra]

I'm using 1.1.4. There are a couple of status code checks for 200 that
fail, but are expected to. But only about 18/30,000 or so..

Thanks!

[Excilys]

There might be 2 explanations:

• message loss. It’s something that might happen if the engine can’t build a request, like expecting an attribute in the session that’s missing. It will be fixed in 1.1.6 (https://github.com/excilys/gatling/issues/423). In 1.1.5 (to be released in a few hours), I’ve added an error log if this happens (but engine will still hang)
• packet loss in the underlying IO layer. Could you try with another IO engine?
• download Grizzly:
• http://search.maven.org/remotecontent?filepath=org/glassfish/grizzly/grizzly-framework/2.2.6/grizzly-framework-2.2.6.jar
• http://search.maven.org/remotecontent?filepath=org/glassfish/grizzly/grizzly-http/2.2.6/grizzly-http-2.2.6.jar
• http://search.maven.org/remotecontent?filepath=org/glassfish/grizzly/grizzly-websockets/2.2.6/grizzly-websockets-2.2.6.jar
• http://search.maven.org/remotecontent?filepath=org/glassfish/gmbal/gmbal-api-only/3.2.0-b003/gmbal-api-only-3.2.0-b003.jar
• http://search.maven.org/remotecontent?filepath=org/glassfish/external/management-api/3.0.0-b012/management-api-3.0.0-b012.jar- drop those jars in Gatling lib dir
• configure Gatling to use Grizzly instead of Netty:
• change Netty into Grizzly in gatling.conf (in conf dir)
  Cheers,

Steph

2012/5/4 Pete Capra <petey.caps@gmail.com>

[Pete_Capra]

Thanks for your help. I'll try both options and get back to you.

[Excilys]

You can also try the new netty:
http://search.maven.org/remotecontent?filepath=io/netty/netty/3.4.3.Final/netty-3.4.3.Final.jar

Release note mentions some events were not being fired.

2012/5/4 Pete Capra <petey.caps@gmail.com>

[Excilys]

Forget about my message and wait for 3.4.4 that should be out very soon: regression issue!
https://github.com/netty/netty/issues/310

2012/5/6 Stéphane Landelle <slandelle@excilys.com>

[Excilys]

Hi Pete,

I’d like to investigate these message loss. Did Grizzly solve the problem for you?

Regards,

Stéphane

2012/5/6 Stéphane Landelle <slandelle@excilys.com>

[Pete_Capra]

Hi Stephane,

I haven't had the opportunity to swap it over yet. I did upgrade to
1.1.6 and a 48 hour test with 1000 users and didn't experience the
issue though. It ran out of memory shortly after starting to compile
the reports - the simulation.log was 7GB! The issue had been occurring
before that point so I took it that the issue was fixed in the newest
version of Netty.

Cheers,

Pete

[Excilys]

Hi Pete,

Thanks for feedback.

Regarding reports generation, I hadn’t expected someone to run such a intensive simulation. Wow!
Do you think you could have a way to upload your simulation.log somewhere so I can try to optimize the reports generation?

Steph

2012/5/17 Pete Capra <petey.caps@gmail.com>