Is it possible to run the load test for a given period of time?

[eriklupander]

Is it possible to run the load test for a given period of time?

[eriklupander]

Hi,

just so I understand you correctly. You would like to be able to do something like this:

actions:
  - http:
      method: GET                                  
      url: http://localhost:8183/courses    
      duration:
        from: 3s500ms
        to: 4s
        exactly: 3s700ms // mutually exclusive with from/to       

If from and to are specified (as Go duration strings), a random duration between from and to is picked, for example 3900ms.

Is your intent that if the actual call to http://localhost:8183/courses takes 1200ms, the action should artificially wait for 3900 - 1200 = 2700 ms in this particular example? If exactly: 3700ms is specified, the action would artificially wait for 3700 -1200 = 2500 ms?

I think the above use-case would be pretty straightforward to implement.

In case the action takes more time than either exactly or from and to, we could control this using a cancellable context.Context set up with WithTimeout in order to halt execution and return an error. This is probably a bit more work to implement properly.

Have I understood your intent correctly? Of course you're free to take a stab at it! I'm not actively working on Gotling, but will of course review and approve PR:s.

[eriklupander]

Hi,

currently Gotling doesn't support running tests for a fixed period of time. It only supports "iterations". I imagine one could approximate the number of "sleep" actions + service latency to come up with a rough estimate on the duration of a full iteration, and then adjust the number of iterations to get an approximate total duration. That would be quite hackish, though.

Adding a fixed duration as an alternative to a fixed number of iterations should be quite simple though. Feel free to do a pull request :)

Cheers,

// Erik

[hakwik]

Sorry, I'm a bit late to the party, I know.

I too would like to see this, and perhaps more importantly the ability to control the duration of the action iteration (i.e. in addition to sleep, be able to say "this iteration should take 3.5 to 4.5 seconds") to better be able to design closed model workloads.

I don't have Go experience but I'm willing to take a stab at it. What would be your suggested implementation?

[hakwik]

Sorry for my very late response! Yes, you have understood my intent correctly.

The way most traditional closed model load testing tools are implemented, if the duration of the request is greater than the duration of the iteration, the iteration simply becomes as long as the request took to complete. This of course means that you're not meeting your calculated load target in the test, but that can be fine (either it doesn't perform or you've miscalculated somewhere).

I'll try to wrap my head around how Gotling works so I can help out.