estatsd is a simple stats aggregation service that periodically dumps data to Graphite: http://graphite.wikidot.com/

NB: Graphite is good, despite the website being a bit ghetto.

Inspired heavily by etsy statsd: http://codeascraft.etsy.com/2011/02/15/measure-anything-measure-everything/

QUICK DEMO

1. Install and configure graphite (quick-ish)
2. Install rebar, have it in your path
3. rebar get-deps
4. rebar compile
5. erl -pa ebin

6. application:start(estatsd). estatsd:increment(foo, 123).

7. Observe graphite now has 1 data point.

USAGE

Add this app to your rebar deps, and make sure it's started somehow eg: application:start(estatsd).

You can configure custom graphite host/port and flush interval using application environment vars. See estatsd_sup for details.

The following calls to estatsd are all gen_server:cast, ie non-blocking.

Counters

estatsd:increment(num_foos).            %% increment num_foos by one

estatsd:decrement(<<"num_bars">>, 3).   %% decrement num_bars by 3

estatsd:increment("tcp.bytes_in", 512). %% increment tcp.bytes_in by 512

Timers

estatsd:timing(sometask, 1534).         %% report that sometask took 1534ms

Or for your convenience:

Start = erlang:now(),
do_sometask(), 
estatsd:timing(sometast, Start).        %% uses now() and now_diff for you

Sampling

Only report 10% of some_frequent_task measurements:

estatsd:timing(some_frequent_task, 12, 0.1) 

NOTES

This could be extended to take a callback for reporting mechanisms. Right now it's hardcoded to stick data into graphite.

Richard Jones [email protected] @metabrew