Phase variables and what they mean in Artillery.js

Nowadays, there are various tools to check the performance metrics of apps, APIs and so on. At Webamboos, we’re using Jmeter and Artillery based on what we need to achieve.

Our performance tests go from simple scripts to complex, but if you’re just starting out, I think you should consider the most basic scenarios. Let’s say you want to check the performance of a GET request and where does it start to crumble, meaning it’s way past it’s bottleneck. For this you’ll need to se Duration, ArrivalRate and rampTo inside the config block of your artillery.yml file.

artillery.yml

config:
 target: 'https://example.com' # Replace with your target URL
 phases:
   - duration: 600
     arrivalRate: 1
     rampTo: 2000
scenarios:
 - flow:
     - get:
         url: '/'

Yesterday, those would’ve been just numbers on the screen, but after this line, you’ll know that a phase has these 3 characteristics:

Duration is the total time (in seconds) the performance test will run
Arrival Rate is the number of new virtual users (requests) per second at the start of the test
RampTo represents the gradual increase of the number of users per second to the specified value during the phase.

In our case, in plain English, our script says that we have smooth ramp-up of load from 1 to 2000 requests per second over the 10-minute(600 seconds) duration.

Bonus:

After testing it out, you can run the config by typing the following in your terminal:

artillery run check-get-endpoint.yml