Load testing experiment

This is a NixOps network and model application to experiment with a hypothetical IOT scaling scenario:

There are a number of devices out in the field which regularly send their measurements to a server and poll for commands.

The question is how will the server perform with a large number of devices and what will be the performance bottleneck.

More discussion in my blog post.

How to run the test harness

To try the test harness on VirtualBox:

$ nixops create -d load-test load-test-network.nix load-test-vbox.nix
$ nixops deploy -d load-test

The various tools can be accessed at the following URLs (IP addresses might vary slightly)

• Locust: http://192.168.56.101:8089/
• Prometheus: http://192.168.56.102:9090
• Grafana: http://192.168.56.102:3000
• Model App: http://192.168.56.102:8080/metrics

Setting up Grafana

Grafana doesn't have a simple JSON export/import for data sources, so there is some manual setup to do.

1. Sign in to Grafana with username admin, password admin.
2. Add a data source
   • Name: prometheus
   • Default: Yes
   • Type: Prometheus
   • URL: http://localhost:9090
   • Access: Proxy
   • Scrape interval: 10s
3. Import a Dashboard
   • Upload the file grafana/dashboard.json.
4. View the dashboard, etc. Upload the dashboard to raintank.io by using the share button at the top of the page and selecting Snapshot.