I'm new to JMeter, so please forgive me if this is an old question. I've read the FAQ, the User Manual, and searched the mailing list archive, but I may have missed something obvious.
I've been trying to set up JMeter to do a distributed load test using some "repurposed" desktops. I've started out with a simple test plan to try to familiarize myself with the program, and I've run into a few problems I can't seem to fix. First, the setup: I have a "server" running the web app, a test control machine running jmeter, and three additional test machines running the jmeter-server script (had some problems with that, but fixed them). All the machines are running JMeter 1.9.1 on Red Hat 9, kernel 2.4.20-20.9, with the Sun 1.4.2_01 JRE. remote_hosts is set to the three test machines in jmeter.properties. I've created a simple test plan consisting of a thread group (50 threads, 30s ramp-up, 100 loops), an HTTP sampler doing a simple get against a servlet on the server, and the simple data writer listener. The machines are all on a switched LAN. The main problem with the setup is that the test controller can't handle the load, and ends up being the bottleneck for the test. With the configuration described above, it gets pegged at 99% CPU utilization until the test is finished. I've tried playing with the number of threads and ramp up period a little, but I can't generate reasonable load on the server before the test control machine gets swamped. It's an Athlon 2000+ with a gig of RAM, so I have some reason to expect it to be able to handle this load. It may also be worth mentioning that in this configuration, the test controller sees about 230-300K/s of traffic, and the server only gets about 80-120K/s and about 4-8% CPU load. I tried running jmeter in console mode (jmeter -n -r -t simpletest.jmx), but kept running into some sort of OutOfBoundsException (sorry, I don't have the stack trace with me at the moment) in an Apache collections class, which caused only one (the last) of the remote testing machines to be used for the test. This of course reduced the load on the test controller (to about 30% CPU usage), but didn't really put any load on the server at all, as two of the remote test machines weren't being used. I'm not really familiar with JMeter as a user, and I haven't looked at the code at all; is there something that I might have misconfigured that could lead to such a high load to just collect samples and write them to disk? Is something else going on? Is it just the case that the remoting in jmeter is too chatty? What can I do to stop the test controller from being the bottleneck, short of buying a 16-way machine? I appreciate any suggestions that anyone can offer. JMeter looks like a great piece of software, and I'd like to make it work! -- Alfred Freur Software Engineer Contrado Partners, LLC --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
