StatsD 
A network daemon that runs on the Node.js platform and
listens for statistics, like counters and timers, sent over UDP or
TCP and sends aggregates to one or more pluggable backend services (e.g.,
Graphite).
Key Concepts
-
buckets
Each stat is in its own "bucket". They are not predefined anywhere. Buckets
can be named anything that will translate to Graphite (periods make folders,
etc) -
values
Each stat will have a value. How it is interpreted depends on modifiers. In
general values should be integers. -
flush
After the flush interval timeout (defined byconfig.flushInterval,
default 10 seconds), stats are aggregated and sent to an upstream backend service.
Installation and Configuration
Docker
Statsd supports docker in two ways:
- The official docker image on docker hub
- Building the image from the bundled Dockerfile
Manual installation
- Install Node.js (All
CurrentandLTSNode.js versions are supported.) - Clone the project
- Create a config file from
exampleConfig.jsand put it somewhere - Start the Daemon:
node stats.js /path/to/config
Usage
The basic line protocol expects metrics to be sent in the format:
<metricname>:<value>, <type>
So the simplest way to send in metrics from your command line if you have
StatsD running with the default UDP server on localhost would be:
echo "foo:1, c", nc -u -w0 127.0.0.1 8125
More Specific Topics
- Metric Types
- Graphite Integration
- Supported Servers
- Supported Backends
- Admin TCP Interface
- Server Interface
- Backend Interface
- Metric Namespacing
- Statsd Cluster Proxy
Debugging
There are additional config variables available for debugging:
debug- log exceptions and print out more diagnostic infodumpMessages- print debug info on incoming messages
For more information, check the exampleConfig.js.
Tests
A test framework has been added using node-unit and some custom code to start
and manipulate statsd. Please add tests under test/ for any new features or bug
fixes encountered. Testing a live server can be tricky, attempts were made to
eliminate race conditions but it may be possible to encounter a stuck state. If
doing dev work, a killall statsd will kill any stray test servers in the
background (don't do this on a production machine!).
Tests can be executed with ./run_tests.sh.
History
statsd was originally written at (Etsy) and released with a blog post
about how it works and why we created it.
Inspiration
StatsD was inspired (heavily) by the project (of the same name) at Flickr.
Here's a post where Cal Henderson described it in depth:
Counting and timing
Cal re-released the code recently:
Perl StatsD