metrics

Documentation

Index

• Variables
• type MetricSystem
  • func NewMetricSystem(interval time.Duration, sysStats bool) *MetricSystem
  • func (ms *MetricSystem) Counter(name string, amount uint64)
  • func (ms *MetricSystem) DeregisterGaugeFunc(name string)
  • func (ms *MetricSystem) Histogram(name string, value float64)
  • func (ms *MetricSystem) RegisterGaugeFunc(name string, f func() float64)
  • func (ms *MetricSystem) Start()
  • func (ms *MetricSystem) StartTimer(name string) TimerToken
  • func (ms *MetricSystem) Stop()
  • func (ms *MetricSystem) StopTimer(token TimerToken) time.Duration
  • func (ms *MetricSystem) SubscribeToProcessedMetrics(metricStream chan *ProcessedMetricSet)
  • func (ms *MetricSystem) SubscribeToRawMetrics(metricStream chan *RawMetricSet)
  • func (ms *MetricSystem) UnsubscribeFromProcessedMetrics(metricStream chan *ProcessedMetricSet)
  • func (ms *MetricSystem) UnsubscribeFromRawMetrics(metricStream chan *RawMetricSet)
• type ProcessedMetricSet
• type RawMetricSet
• type TimerToken

Examples

• MetricSystem

Variables

var Metrics = NewMetricSystem(60*time.Second, true)

Metrics is the default metric system, which collects and broadcasts metrics to subscribers once every 60 seconds. Also includes default system stats.

Types

type MetricSystem

type MetricSystem struct {
	// contains filtered or unexported fields
}

MetricSystem facilitates the collection and distribution of metrics.

Example

ms := NewMetricSystem(time.Microsecond, true)
ms.Start()
myMetricStream := make(chan *ProcessedMetricSet, 2)
ms.SubscribeToProcessedMetrics(myMetricStream)

timeToken := ms.StartTimer("submit_metrics")
ms.Counter("range_splits", 1)
ms.Histogram("some_ipc_latency", 123)
ms.StopTimer(timeToken)

processedMetricSet := <-myMetricStream
ms.UnsubscribeFromProcessedMetrics(myMetricStream)

m := processedMetricSet.Metrics

example := []struct {
	Name  string
	Value float64
}{
	{
		"total range splits during the process lifetime",
		m["range_splits"],
	}, {
		"range splits in this period",
		m["range_splits_rate"],
	}, {
		"some_ipc 99.9th percentile",
		m["some_ipc_latency_99.9"],
	}, {
		"some_ipc max",
		m["some_ipc_latency_max"],
	}, {
		"some_ipc calls this period",
		m["some_ipc_latency_count"],
	}, {
		"some_ipc calls during the process lifetime",
		m["some_ipc_latency_agg_count"],
	}, {
		"some_ipc total latency this period",
		m["some_ipc_latency_sum"],
	}, {
		"some_ipc mean this period",
		m["some_ipc_latency_avg"],
	}, {
		"some_ipc aggregate man",
		m["some_ipc_latency_agg_avg"],
	}, {
		"time spent submitting metrics this period",
		m["submit_metrics_sum"],
	}, {
		"number of goroutines",
		m["sys.NumGoroutine"],
	}, {
		"time spent in GC",
		m["sys.PauseTotalNs"],
	},
}
for _, nameValue := range example {
	var result string
	if nameValue.Value == float64(0) {
		result = "NOT present"
	} else {
		result = "present"
	}
	fmt.Println(nameValue.Name, result)
}
ms.Stop()

Output:

total range splits during the process lifetime present
range splits in this period present
some_ipc 99.9th percentile present
some_ipc max present
some_ipc calls this period present
some_ipc calls during the process lifetime present
some_ipc total latency this period present
some_ipc mean this period present
some_ipc aggregate man present
time spent submitting metrics this period present
number of goroutines present
time spent in GC present

func NewMetricSystem

func NewMetricSystem(interval time.Duration, sysStats bool) *MetricSystem

NewMetricSystem returns a new metric system that collects and broadcasts metrics after each interval.

func (*MetricSystem) Counter

func (ms *MetricSystem) Counter(name string, amount uint64)

Counter is used for recording a running count of the total occurrences of a particular event. A rate is also exported for the amount that a counter has increased during an interval of this MetricSystem.

func (*MetricSystem) DeregisterGaugeFunc

func (ms *MetricSystem) DeregisterGaugeFunc(name string)

DeregisterGaugeFunc deregisters a function for the <name> metric.

func (*MetricSystem) Histogram

func (ms *MetricSystem) Histogram(name string, value float64)

Histogram is used for generating rich metrics, such as percentiles, from periodically occurring continuous values.

func (*MetricSystem) RegisterGaugeFunc

func (ms *MetricSystem) RegisterGaugeFunc(name string, f func() float64)

RegisterGaugeFunc registers a function to be called at each interval whose return value will be used to populate the <name> metric.

func (*MetricSystem) Start

func (ms *MetricSystem) Start()

Start spawns a goroutine for merging metrics into caches from metric submitters, and a reaper goroutine that harvests metrics at the default interval of every 60 seconds.

func (*MetricSystem) StartTimer

func (ms *MetricSystem) StartTimer(name string) TimerToken

StartTimer begins a timer and returns a token which is required for halting the timer. This allows for concurrent timings under the same name.

func (*MetricSystem) Stop

func (ms *MetricSystem) Stop()

Stop shuts down a MetricSystem

func (*MetricSystem) StopTimer

func (ms *MetricSystem) StopTimer(token TimerToken) time.Duration

StopTimer takes a token given by StartTimer, stops the timer, submits a Histogram of its duration in nanoseconds, and returns its duration in nanoseconds.

func (*MetricSystem) SubscribeToProcessedMetrics

func (ms *MetricSystem) SubscribeToProcessedMetrics(
	metricStream chan *ProcessedMetricSet)

SubscribeToProcessedMetrics registers a channel to receive ProcessedMetricSets periodically generated by reaper at each interval.

func (*MetricSystem) SubscribeToRawMetrics

func (ms *MetricSystem) SubscribeToRawMetrics(metricStream chan *RawMetricSet)

SubscribeToRawMetrics registers a channel to receive RawMetricSets periodically generated by reaper at each interval.

func (*MetricSystem) UnsubscribeFromProcessedMetrics

func (ms *MetricSystem) UnsubscribeFromProcessedMetrics(
	metricStream chan *ProcessedMetricSet)

UnsubscribeFromProcessedMetrics registers a channel to receive ProcessedMetricSets periodically generated by reaper at each interval.

func (*MetricSystem) UnsubscribeFromRawMetrics

func (ms *MetricSystem) UnsubscribeFromRawMetrics(
	metricStream chan *RawMetricSet)

UnsubscribeFromRawMetrics registers a channel to receive RawMetricSets periodically generated by reaper at each interval.

type ProcessedMetricSet

type ProcessedMetricSet struct {
	Time    time.Time
	Metrics map[string]float64
}

ProcessedMetricSet contains human-readable metrics that may also be suitable for storage in time-series databases.

type RawMetricSet

type RawMetricSet struct {
	Time       time.Time
	Counters   map[string]uint64
	Rates      map[string]uint64
	Histograms map[string]map[int16]*uint64
	Gauges     map[string]float64
}

RawMetricSet contains metrics in a form that supports generation of percentiles and other rich statistics.

type TimerToken

type TimerToken struct {
	Name  string
	ID    uint32
	Start time.Time
}

TimerToken facilitates concurrent timings of durations of the same label.