alexellis / locust-openfaas

Locust load-testing tool on OpenFaaS

locust-openfaas

Run the locust.io load-testing tool on OpenFaaS with Kubernetes, Docker Swarm, Nomad, DC/OS or Rancher Cattle.

This sample function shows how to run a load-test with the locust tool. OpenFaaS is Making Serverless Functions Simple.

What is Locust?

Locust is an easy-to-use, distributed, user load testing tool. It is intended for load-testing web sites (or other systems) and figuring out how many concurrent users a system can handle. The idea is that during a test, a swarm of locusts will attack your website. The behavior of each locust (or test user if you will) is defined by you and the swarming process is monitored from a web UI in real-time. This will help you battle test and identify bottlenecks in your code before letting real users in.

How do you use it with OpenFaaS?

Pre-reqs:

• Install Docker
• Deploy OpenFaaS and extend the built-in timeouts
• Install faas-cli
• Clone the GitHub repo

Usage

This example function shows that it's possible to run a locust load-test through OpenFaaS.

Usage:

$ faas-cli build
$ faas-cli deploy
$ echo -n https://requestb.in/uhphaiuh | \
  faas-cli invoke locust > results.csv && \
  cat results.csv

This will take several seconds to build up to the full load and will return the whole output to your client when done as a CSV result file in plain-text.

"Method","Name","# requests","# failures","Median response time","Average response time","Min response time","Max response time","Average Content Size","Requests/s"
"GET","/uhphaiuh",1099,0,340,702,141,5702,2,213.43
"None","Total",1099,0,340,702,141,5702,2,213.43

You will also need to up the timeouts on your OpenFaaS gateway.

locust-openfaas's Issues

Open file limit

Locust likes to open alot of files while running, however the limit is set to 1024.

How do we increase the open file limit for this openfaas function?

Increasing the open file limit on the whole system does not seem to work.