code for the example used in AppOptics runtime metrics eventloop blog

First, this package only runs on Linux. If you run Linux or want to set up a docker image feel free to clone it and play with it.

install

$ git clone https://github.com/appoptics/node-event-loop-blog

$ cd node-event-loop-blog

$ npm install

It has only three direct dependencies: the AppOptics APM agent, express, and multiload - a CLI tool for generating loads against a server.

running it

It's designed to be run from terminal windows.

Make sure you have APPOPTICS_SERVICE_KEY defined in the environment. That's necessary for appoptics-apm and for reporting application-specific metrics. If you don't have a service key see the following section.

In one terminal execute $ npm start to start the server. It is hardcoded to run on localhost:8888 so change it if you need to.

In another terminal execute $ npm run get-sync or $npm run get-async to hit the endpoint you choose. It will output the server response and append curl's timing to the end of the line.

If you want to run a continuous load against it execute $ npm run multiload.

if you don't have an AppOptics account

Get a free dev edition account to view the data in real time. That's a free account limited to development use, not a just free trial.