Awesome

Katja VM Stats

Easily send information about the Erlang VM to Riemann.

Status

This is beta software. Things might still change in ways that break everything.

Configuration

% Defaults
[
  {katja_vmstats, [
    {service, "katja_vmstats"},
    {transport, config},
    {send_async, false},
    {async_sample_rate, 1.0},
    {delay_collection, 0},
    {collector, [
      [
        {interval, 1000},
        {metrics, [
          error_logger_message_queue,
          loaded_modules,
          memory_atoms,
          memory_binaries,
          memory_ets,
          memory_processes,
          memory_system,
          memory_total,
          port_count,
          port_limit,
          port_utilization,
          process_count,
          process_limit,
          process_utilization,
          run_queue
        ]}
      ]
    ]}
  ]}
].

service: Base value for the service field of events

transport: The message transport that should be used (supported: config, detect, udp, tcp)

send_async: Wether or not data should be send to Riemann asynchronously

async_sample_rate: Sample rate that will be used if messages are send asynchronously (useful if not every collection has to be send to Riemann all the time)

delay_collection: Delays the initial collection of metrics by the specified amount of milliseconds

collector: A list of metrics that will be collected in the given interval(s)

Examples

In general, you don't have to do anything (apart from maybe changing the default configuration) to make katja_vmstats work.

A list of all available, collectable metrics can be found in the katja_vmstats_metrics module. Every exported function defined in that module can be collected.

Collecting metrics manually

ok = katja_vmstats:collect(ets_count),
ok = katja_vmstats:collect([ets_limit, ets_utilization]),
ok = katja_vmstats:collect({"katja_vmstats_collector_message_queue", message_queue, [katja_vmstats_collector]}),
ok = katja_vmstats:collect({"process_limit", erlang, system_info, [process_limit]}).

katja_vmstats:collect/1 takes a single katja_vmstats:metric() or a list of katja_vmstats:metric(). The following "formats" are supported:

atom(): A function defined and exported in the katja_vmstats_metrics module.
{iolist(), atom(), [any()]}: A function defined and exported in the katja_vmstats_metrics module. The first tuple field is the name of the metric, the second and the third field are the FA part of MFA.
{iolist(), module(), atom(), [any()]}: Any function in any module that returns a number(). The first tuple field is the name of the metric, the following fields are MFA.

Working with collections

AllCollections = katja_vmstats:get_collection(all), % => [[{name, config}, {metrics, […]}, {interval, 1000}, {send_async, false}, {async_sample_rate, 1.0}]]
ConfigCollection = katja_vmstats:get_collection(config). % => [[{name, config}, {metrics, […]}, {interval, 1000}, {send_async, false}, {async_sample_rate, 1.0}]]

You can get a list of registered collections using katja_vmstats:get_collection/1. If a collection consists of multiple katja_vmstats:collection() entries, it will show up multiple times in the returned list.

The collections that are specified via configuration options will always be registered under the name config. You can get all intervals by setting the name to all.

Metrics = [{"reductions_process", reductions_process, [katja_vmstats_collector]}],
ok = katja_vmstats:start_collection(demo, [{interval, 1000}, {metrics, Metrics}]),
AllCollections = katja_vmstats:get_collection(all), % => [[…], […]]
DemoCollection = katja_vmstats:get_collection(demo). % => [[{name, demo}, {metrics, […]}, {interval, 1000}, {send_async, false}, {async_sample_rate, 1.0}]]

You can start new collections using katja_vmstats:start_collection/2. The first argument is the name of the collection and the second argument is a property list (or a list of property lists) in the format of katja_vmstats:collection(). The name attribute of the property list will be ignored.

ok = katja_vmstats:stop_collection(demo),
AllCollections = katja_vmstats:get_collection(all). % => [[{name, config}, {metrics, […]}, {interval, 1000}, {send_async, false}, {async_sample_rate, 1.0}]]

Collections can be stopped using katja_vmstats:stop_collection/1. You can set the name to all in order to stop all registered collections.

Resources

Generated EDoc (All Versions)

Related Projects

Katja - A simple Riemann client written in Erlang

License

ISC.

Copyright (c) 2014-2016, Daniel Kempkens <daniel@kempkens.io>
Copyright (c) 2017-2020, Dave Cottlehuber <dch@skunkwerks.at>

Permission to use, copy, modify, and/or distribute this software for any purpose
with or without fee is hereby granted, provided that the above copyright notice
and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
THIS SOFTWARE.