>From my experience the CPU on the load generator should remain idle if you want to get stable results from the test, such results where you can actually compare with previous tests without the question of whether the load generator is overloaded.
A gross number I go with is at the range of 30% CPU usage or less on the JMeter host. Of-course you always need to take into consideration the memory is not swapped in OS level (so it can be ~100% RAM usage). One other thing is JMeter JVM GC workloads, which should be minimal, you should make sure JMeter is not spending too much effort on GC, no matter what's the configured heap size. But that's a good question, I'd also like to know what others are doing. Shmuel Krakower. www.Beatsoo.org - re-use your jmeter scripts for application performance monitoring from worldwide locations for free. On Wed, Oct 9, 2013 at 5:08 AM, Tim Koopmans <[email protected]> wrote: > At flood.io we find a better measure of performance and impact on test > results is JVM heap utilization. > > For example, this benchmark https://flood.io/954b7d5d79f134 shows > degradation of response time over time as heap utilization increases > > https://github.com/flood-io/flood-loadtest/blob/master/benchmarks/results/954b7d5d79f134.md > > Having said that we were running 30K users on a single JVM. You can find > out more about our benchmarks here: > https://flood.io/blog/11-benchmarking-jmeter-and-gatling > > You can correlate increased CPU of course with heavy resource utilization > within the JVM, but looking at CPU alone is like trying to measure rainfall > by listening to it fall on the roof. > > Regards, > Tim > > > > > Tim Koopmans > +61 417 262 008 > > <http://altentee.com/> > > The Automation Company > > > > On Wed, Oct 9, 2013 at 1:00 PM, Ophir.Prusak <[email protected] > >wrote: > > > I'm running a JMeter test using JMeter on an amazon EC2 instance (large) > as > > the load server using 1,000 threads. The load server CPU is steady at > about > > 90% utilization and memory is at 70%. > > > > Is there a rule of thumb regarding at what point does the server not > having > > enough resources impact test results? > > > > Regarding CPU would you say 90%? 95% 99%? Regarding Memory would you say > > 90%? 95% 99%? > > > > Thanks Ophir > > > > > > > > -- > > View this message in context: > > > http://jmeter.512774.n5.nabble.com/Is-my-load-server-causing-results-to-be-in-accurate-tp5718385.html > > Sent from the JMeter - User mailing list archive at Nabble.com. > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [email protected] > > For additional commands, e-mail: [email protected] > > > > >
