gostatsd

An implementation of Etsy's statsd in Go, based on original code from @kisielk.

The project provides both a server called "gostatsd" which works much like Etsy's version, but also provides a library for developing customized servers.

Backends are pluggable and only need to support the backend interface.

Being written in Go, it is able to use all cores which makes it easy to scale up the server based on load. The server can also be run HA and be scaled out, see Load balancing and scaling out.

Building the server

From the gostatsd directory run make build. The binary will be built in build/bin/<arch>/gostatsd.

You will need to install the build dependencies by running make setup in the gostatsd directory. This must be done before the first build, and again if the dependencies change.

If you are unable to build gostatsd please try running make setup again before reporting a bug.

Running the server

gostatsd --help gives a complete description of available options and their defaults. You can use make run to run the server with just the stdout backend to display info on screen. You can also run through docker by running make run-docker which will use docker-compose to run gostatsd with a graphite backend and a grafana dashboard.

Configuring backends and cloud providers

Backends and cloud providers are configured using toml, json or yaml configuration file passed via the --config-path flag. For all configuration options see source code of the backends you are interested in. Configuration file might look like this:

[graphite]
	address = "192.168.99.100:2003"

[datadog]
	api_key = "my-secret-key" # Datadog API key required.

[statsdaemon]
	address = "docker.local:8125"
	disable_tags = false

[aws]
	max_retries = 4

Sending metrics

The server listens for UDP packets on the address given by the --metrics-addr flag, aggregates them, then sends them to the backend servers given by the --backends flag (comma separated list of backend names).

Currently supported backends are:

• graphite
• datadog
• statsd
• stdout

The format of each metric is:

<bucket name>:<value>|<type>\n

• <bucket name> is a string like abc.def.g, just like a graphite bucket name
• <value> is a string representation of a floating point number
• <type> is one of c, g, or ms for "counter", "gauge", and "timer" respectively.

A single packet can contain multiple metrics, each ending with a newline.

Optionally, gostatsd supports sample rates and tags (unused):

• <bucket name>:<value>|c|@<sample rate>\n where sample rate is a float between 0 and 1
• <bucket name>:<value>|c|@<sample rate>|#<tags>\n where tags is a comma separated list of tags
• or <bucket name>:<value>|<type>|#<tags>\n where tags is a comma separated list of tags

Tags format is: simple or key:value.

A simple way to test your installation or send metrics from a script is to use echo and the netcat utility nc:

echo 'abc.def.g:10|c' | nc -w1 -u localhost 8125

Monitoring

Currently you can get some basic idea of the status of the server by visiting the address given by the --console-addr option with your web browser.

Load balancing and scaling out

It is possible to run multiple versions of gostatsd behind a load balancer by having them send their metrics to another gostatsd backend which will then send to the final backends.

Memory allocation for read buffers

By default gostatsd will batch read multiple packets to optimise read performance. The amount of memory allocated for these read buffers is determined by the config options:

max-readers * receive-batch-size * 64KB (max packet size)

The metric avg_packets_in_batch can be used to track the average number of datagrams received per batch, and the --receive-batch-size flag used to tune it. There may be some benefit to tuning the --max-readers flag as well.

Using the library

In your source code:

import "github.com/atlassian/gostatsd/pkg/statsd"

Documentation can be found via go doc github.com/atlassian/gostatsd/pkg/statsd or at https://godoc.org/github.com/atlassian/gostatsd/pkg/statsd

Contributors

Pull requests, issues and comments welcome. For pull requests:

• Add tests for new features and bug fixes
• Follow the existing style
• Separate unrelated changes into multiple pull requests

See the existing issues for things to start contributing.

For bigger changes, make sure you start a discussion first by creating an issue and explaining the intended change.

Atlassian requires contributors to sign a Contributor License Agreement, known as a CLA. This serves as a record stating that the contributor is entitled to contribute the code/documentation/translation to the project and is willing to have it used in distributions and derivative works (or is willing to transfer ownership).

Prior to accepting your contributions we ask that you please follow the appropriate link below to digitally sign the CLA. The Corporate CLA is for those who are contributing as a member of an organization and the individual CLA is for those contributing as an individual.

• CLA for corporate contributors
• CLA for individuals

License

Copyright (c) 2012 Kamil Kisiel. Copyright @ 2016-2017 Atlassian Pty Ltd and others.

Licensed under the MIT license. See LICENSE file.