servlet capacity testing: load generator?

[Inevitability]

hello myBB,
Does anyone know of a free/open-source http load generator that I can use to test capacity of a servlet?
Thing is: it must be able to read responses and make decisions based on that.
Example:
1. Try http://myurl.net/call1
a. If: response = {some XML} then proceed to 2
b. Else: mark as error and stop
2. Try http://myurl.net/call2
a. If response = {some XML} then proceed to 3
b. Else: mark as error and stop
3. Try http://myurl.net/call3
a. If response = {some XML code} then end
b. Else: mark as error and stop
The guys in the testing department have Mercury LoadRunner (which works well) but it's on a very limited licence, and I need to simulate a lot more load.

 

[icyrus]

You could try Grinder but I've never used it so can't say whether it it will meet your needs.

 

[stevenv]

Write a simple multi-threaded client that makes HTTP requests, processes the response and then terminates? You could run multiple clients on multiple systems to spread the requests if you want a large load.

 

[Inevitability]

Write a simple multi-threaded client that makes HTTP requests, processes the response and then terminates? You could run multiple clients on multiple systems to spread the requests if you want a large load.

That's sort of what we did yesterday afternoon (...just for kicks). One of the guys scripted a looped HTTP GET with varying parameters and we created multiple instances to simulate parallel traffic. It didn't quite give us the result we'd expected... the count of successful responses seemed a lot higher than we'd got previously on the live webserver!... but we hadn't logged the response time so I'm sure the requests processed very slowly.
I'll look into writing the "load-generator" in Java (thing is, we're not proper developers... especially me... I know some basics and I just Google the rest!! )
But thanks for the suggestion... I'll definitely look into it today... it should be good fun.