mirror of
https://github.com/moby/moby.git
synced 2022-11-09 12:21:53 -05:00
69 lines
2.4 KiB
Markdown
69 lines
2.4 KiB
Markdown
|
go-metrics
|
||
|
|
==========
|
||
|
|
|
||
|
|
This library provides a `metrics` package which can be used to instrument code,
|
||
|
|
expose application metrics, and profile runtime performance in a flexible manner.
|
||
|
|
|
||
|
|
Sinks
|
||
|
|
=====
|
||
|
|
|
||
|
|
The `metrics` package makes use of a `MetricSink` interface to support delivery
|
||
|
|
to any type of backend. Currently the following sinks are provided:
|
||
|
|
|
||
|
|
* StatsiteSink : Sinks to a statsite instance (TCP)
|
||
|
|
* StatsdSink: Sinks to a statsd / statsite instance (UDP)
|
||
|
|
* InmemSink : Provides in-memory aggregation, can be used to export stats
|
||
|
|
* FanoutSink : Sinks to multiple sinks. Enables writing to multiple statsite instances for example.
|
||
|
|
* BlackholeSink : Sinks to nowhere
|
||
|
|
|
||
|
|
In addition to the sinks, the `InmemSignal` can be used to catch a signal,
|
||
|
|
and dump a formatted output of recent metrics. For example, when a process gets
|
||
|
|
a SIGUSR1, it can dump to stderr recent performance metrics for debugging.
|
||
|
|
|
||
|
|
Examples
|
||
|
|
========
|
||
|
|
|
||
|
|
Here is an example of using the package:
|
||
|
|
|
||
|
|
func SlowMethod() {
|
||
|
|
// Profiling the runtime of a method
|
||
|
|
defer metrics.MeasureSince([]string{"SlowMethod"}, time.Now())
|
||
|
|
}
|
||
|
|
|
||
|
|
// Configure a statsite sink as the global metrics sink
|
||
|
|
sink, _ := metrics.NewStatsiteSink("statsite:8125")
|
||
|
|
metrics.NewGlobal(metrics.DefaultConfig("service-name"), sink)
|
||
|
|
|
||
|
|
// Emit a Key/Value pair
|
||
|
|
metrics.EmitKey([]string{"questions", "meaning of life"}, 42)
|
||
|
|
|
||
|
|
|
||
|
|
Here is an example of setting up an signal handler:
|
||
|
|
|
||
|
|
// Setup the inmem sink and signal handler
|
||
|
|
inm := NewInmemSink(10*time.Second, time.Minute)
|
||
|
|
sig := DefaultInmemSignal(inm)
|
||
|
|
metrics.NewGlobal(metrics.DefaultConfig("service-name"), inm)
|
||
|
|
|
||
|
|
// Run some code
|
||
|
|
inm.SetGauge([]string{"foo"}, 42)
|
||
|
|
inm.EmitKey([]string{"bar"}, 30)
|
||
|
|
|
||
|
|
inm.IncrCounter([]string{"baz"}, 42)
|
||
|
|
inm.IncrCounter([]string{"baz"}, 1)
|
||
|
|
inm.IncrCounter([]string{"baz"}, 80)
|
||
|
|
|
||
|
|
inm.AddSample([]string{"method", "wow"}, 42)
|
||
|
|
inm.AddSample([]string{"method", "wow"}, 100)
|
||
|
|
inm.AddSample([]string{"method", "wow"}, 22)
|
||
|
|
|
||
|
|
....
|
||
|
|
|
||
|
|
When a signal comes in, output like the following will be dumped to stderr:
|
||
|
|
|
||
|
|
[2014-01-28 14:57:33.04 -0800 PST][G] 'foo': 42.000
|
||
|
|
[2014-01-28 14:57:33.04 -0800 PST][P] 'bar': 30.000
|
||
|
|
[2014-01-28 14:57:33.04 -0800 PST][C] 'baz': Count: 3 Min: 1.000 Mean: 41.000 Max: 80.000 Stddev: 39.509
|
||
|
|
[2014-01-28 14:57:33.04 -0800 PST][S] 'method.wow': Count: 3 Min: 22.000 Mean: 54.667 Max: 100.000 Stddev: 40.513
|
||
|
|
|