Hi Phillppe, Like I mentioned, I came in late on the thread.. So, I think the question here isn't can 10 thread generate 21 req/s but more to the point, if I need 21 req/s how can I setup JMeter to deliver this without having the server interfere with it doing so. Given that server response time in this case could be a huge source of CO, you'd not want to have the harness depend upon a thread being freed by the server before a new request could be issued.
Regards, Kirk On 2013-10-03, at 4:02 PM, Philippe Mouawad <[email protected]> wrote: > Hello Kirk, > In this case , the question was can 10 Threads generate 21 req/s ? Do you > agree that it is quite possible ? > User was not saying he had a variation. > I understand Coordinated Omission (and thanks for your contribution to > this) but I am not sure it's the case here , or do I misunderstand ? > > Thanks > > > On Thu, Oct 3, 2013 at 3:58 PM, Kirk Pepperdine > <[email protected]>wrote: > >> Hi all, >> >> Jumping in on this thread late but (very bluntly) if your test harness >> throughput is dependent upon the response time of your application, you >> test system is broken. This is one of the conditions that we've recently >> named coordinated omission (CO). It is a state where the test harness and >> the server (accidentally or unintentionally) collaborate to miss injecting >> samples when they should have been injected. The net result is that the >> harness backs off allowing the server to drain and that in turn allows your >> server to report on numbers that are much better than they would be in >> reality. From a performance testing point of view, the reduced load is akin >> to a scale down study of your system. Scale down studies often produce >> different results than testing at scale. It is but one of the many ways >> UATs fail to recognize problems that leak out into prod but it's an >> important one. >> >> How to fix this? For starters, always set the loop count for a thread to >> 1. Set the number of threads to the number of transactions you want to run >> and then set the warmup time to the duration of the test. This won't fix >> all of the problems that come with using JMeter but it gets rid of one of >> the bigger problems. BTW, all of the other tools in the space suffer from >> the exact same issues. >> >> Regards, >> Kirk >> >> >> On 2013-10-02, at 9:05 PM, Philippe Mouawad <[email protected]> >> wrote: >> >>> Hello, >>> Of course you can generate even much more than 21req / s. >>> If fully depends on your response times. >>> >>> Want to test: >>> - Create a mirror server listening on 8081 >>> - Create an HTTP Sampler hitting localhost:8081 >>> - Add only an aggregate report >>> >>> >>> Running on a last generation Mac Book Pro with default configuration => >> 517 >>> req/s . >>> >>> This test is stupid but just to confirm you can hit this rate. >>> The results you mention are strange and I think wrong. >>> >>> Regards >>> Philippe >>> @philmdot >>> >>> >>> >>> >>> >>> On Wed, Oct 2, 2013 at 12:47 PM, bobMeliev >>> <[email protected]<javascript:_e({}, 'cvml', '[email protected]');> >>>> wrote: >>> >>>> Nope. Even by default Dummy Sampler couldn't generate such load. >> Screenshot >>>> attached. >>>> >>>> <http://jmeter.512774.n5.nabble.com/file/n5718286/screenshot_233.png> >>>> >>>> 21 req/s is huge load just for 10 users. Check this report >>>> >>>> >> http://blazemeter.com/blog/increasing-productivity-wordpress-site-when-using-blazemeter-its-easy-task >>>> with 300 users generated only 5 req/s load and with such load CPU was >> 75% >>>> busy. >>>> >>>> >>>> >>>> >>>> -- >>>> View this message in context: >>>> >> http://jmeter.512774.n5.nabble.com/Understanding-Hits-per-second-tp5718263p5718286.html >>>> Sent from the JMeter - User mailing list archive at Nabble.com. >>>> >>>> --------------------------------------------------------------------- >>>> To unsubscribe, e-mail: >>>> [email protected]<javascript:_e({}, >> 'cvml', '[email protected]');> >>>> For additional commands, e-mail: >>>> [email protected]<javascript:_e({}, >> 'cvml', '[email protected]');> >>>> >>>> >>> >>> >>> -- >>> Cordialement. >>> Philippe Mouawad. >>> >>> >>> >>> >>> -- >>> Cordialement. >>> Philippe Mouawad. >> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: [email protected] >> For additional commands, e-mail: [email protected] >> >> > > > -- > Cordialement. > Philippe Mouawad. --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
