# VMStatsEx

This is a tiny wrapper on top of the awesome [ferd/vmstats](https://github.com/ferd/vmstats)
package which pushes a lot of useful metrics about the erlang runtime using the
[statix](https://github.com/lexmag/statix) library to a StatsD server.

## Installation

  1. Include this in your `mix.exs`. That's it you are ready to go. This pushes data to localhost:8125/udp
```elixir
def deps do
  [
    {:vmstats_ex, "~> 0.1.0"}
  ]
end
```

  2. Configure vmstats.
```elixir
# vmstats default config: https://github.com/ferd/vmstats#configuration
config :vmstats, sink: VMStatsEx.Sink
  sched_time: true,
  base_key: "vmstats",
  key_seperator: ".",
  interval: 1000, # in ms
  memory_metrics: [{total, total}, {processes_used, procs_used}, {atom_used, atom_used}, {binary, binary}, {ets, ets}]
```

  3. Configure statix to send data to your StatsD server
```elixir
config :statix,
  prefix: "my_app",
  host: "localhost",
  port: 8125
```

## Testing

Testing that you are metrics are being sent can be a pain sometimes, just run the following
script on your local computer and start an iex session with your project that uses `vmstats_ex`
and you should be able to see your metrics on Datadog.

```sh
# local datadog agent using docker
docker run \
  --name dd-agent \
  -v /var/run/docker.sock:/var/run/docker.sock:ro \
  -v /proc/:/host/proc/:ro \
  -v /sys/fs/cgroup/:/host/sys/fs/cgroup:ro \
  -e DD_API_KEY=<YOUR_DATADOG_API_KEY> \
  -e DD_DOGSTATSD_NON_LOCAL_TRAFFIC=true \
  -p 8125:8125/udp \
  datadog/agent:latest
```