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pythonload-testinglocust

Locust - Python load testing. No documentation provided; so what do the ramping terms mean?


Locust gives the option to ramp up wherein you need to enter certain input details. I didn't find any documentation explaining the following terms whereas the other ones (not mentioned) seem self-explanatory:

Ramping

Hatch stride
Precision (min value of hatch stride)
Calibration time (seconds)
Percentile (%)
Max percentile response time (ms)
Accepted fail ratio (%)

Thanks!


Solution

  • The ramping feature of Locust was experimental, and has been removed from the latest version.

    The idea with the ramping feature was that you would enter an acceptable failed request ratio (Accepted fail ratio), and a maximum acceptable response time (Max percentile response time) for a given percentile of users (Percentile), and then it would gradually ramp up the number of simultaneous users for as long as those limits weren't exceeded. So the purpose was to automatically find out the number of users that a system could handle. However it never worked really well in practice and as Locust evolved the ramping feature was somewhat forgotten, and eventually removed.

    Hatch and Precision had to do with how fast new users would be spawned, and Calibration time was the time frame that that was used to measure the fail ratio and response time for a given percentile, before either spawning or killing more users.