open-consul/vendor/github.com/armon/go-metrics/metrics.go

294 lines
7.6 KiB
Go

package metrics
import (
"runtime"
"strings"
"time"
"github.com/hashicorp/go-immutable-radix"
)
type Label struct {
Name string
Value string
}
func (m *Metrics) SetGauge(key []string, val float32) {
m.SetGaugeWithLabels(key, val, nil)
}
func (m *Metrics) SetGaugeWithLabels(key []string, val float32, labels []Label) {
if m.HostName != "" {
if m.EnableHostnameLabel {
labels = append(labels, Label{"host", m.HostName})
} else if m.EnableHostname {
key = insert(0, m.HostName, key)
}
}
if m.EnableTypePrefix {
key = insert(0, "gauge", key)
}
if m.ServiceName != "" {
if m.EnableServiceLabel {
labels = append(labels, Label{"service", m.ServiceName})
} else {
key = insert(0, m.ServiceName, key)
}
}
allowed, labelsFiltered := m.allowMetric(key, labels)
if !allowed {
return
}
m.sink.SetGaugeWithLabels(key, val, labelsFiltered)
}
func (m *Metrics) EmitKey(key []string, val float32) {
if m.EnableTypePrefix {
key = insert(0, "kv", key)
}
if m.ServiceName != "" {
key = insert(0, m.ServiceName, key)
}
allowed, _ := m.allowMetric(key, nil)
if !allowed {
return
}
m.sink.EmitKey(key, val)
}
func (m *Metrics) IncrCounter(key []string, val float32) {
m.IncrCounterWithLabels(key, val, nil)
}
func (m *Metrics) IncrCounterWithLabels(key []string, val float32, labels []Label) {
if m.HostName != "" && m.EnableHostnameLabel {
labels = append(labels, Label{"host", m.HostName})
}
if m.EnableTypePrefix {
key = insert(0, "counter", key)
}
if m.ServiceName != "" {
if m.EnableServiceLabel {
labels = append(labels, Label{"service", m.ServiceName})
} else {
key = insert(0, m.ServiceName, key)
}
}
allowed, labelsFiltered := m.allowMetric(key, labels)
if !allowed {
return
}
m.sink.IncrCounterWithLabels(key, val, labelsFiltered)
}
func (m *Metrics) AddSample(key []string, val float32) {
m.AddSampleWithLabels(key, val, nil)
}
func (m *Metrics) AddSampleWithLabels(key []string, val float32, labels []Label) {
if m.HostName != "" && m.EnableHostnameLabel {
labels = append(labels, Label{"host", m.HostName})
}
if m.EnableTypePrefix {
key = insert(0, "sample", key)
}
if m.ServiceName != "" {
if m.EnableServiceLabel {
labels = append(labels, Label{"service", m.ServiceName})
} else {
key = insert(0, m.ServiceName, key)
}
}
allowed, labelsFiltered := m.allowMetric(key, labels)
if !allowed {
return
}
m.sink.AddSampleWithLabels(key, val, labelsFiltered)
}
func (m *Metrics) MeasureSince(key []string, start time.Time) {
m.MeasureSinceWithLabels(key, start, nil)
}
func (m *Metrics) MeasureSinceWithLabels(key []string, start time.Time, labels []Label) {
if m.HostName != "" && m.EnableHostnameLabel {
labels = append(labels, Label{"host", m.HostName})
}
if m.EnableTypePrefix {
key = insert(0, "timer", key)
}
if m.ServiceName != "" {
if m.EnableServiceLabel {
labels = append(labels, Label{"service", m.ServiceName})
} else {
key = insert(0, m.ServiceName, key)
}
}
allowed, labelsFiltered := m.allowMetric(key, labels)
if !allowed {
return
}
now := time.Now()
elapsed := now.Sub(start)
msec := float32(elapsed.Nanoseconds()) / float32(m.TimerGranularity)
m.sink.AddSampleWithLabels(key, msec, labelsFiltered)
}
// UpdateFilter overwrites the existing filter with the given rules.
func (m *Metrics) UpdateFilter(allow, block []string) {
m.UpdateFilterAndLabels(allow, block, m.AllowedLabels, m.BlockedLabels)
}
// UpdateFilterAndLabels overwrites the existing filter with the given rules.
func (m *Metrics) UpdateFilterAndLabels(allow, block, allowedLabels, blockedLabels []string) {
m.filterLock.Lock()
defer m.filterLock.Unlock()
m.AllowedPrefixes = allow
m.BlockedPrefixes = block
if allowedLabels == nil {
// Having a white list means we take only elements from it
m.allowedLabels = nil
} else {
m.allowedLabels = make(map[string]bool)
for _, v := range allowedLabels {
m.allowedLabels[v] = true
}
}
m.blockedLabels = make(map[string]bool)
for _, v := range blockedLabels {
m.blockedLabels[v] = true
}
m.AllowedLabels = allowedLabels
m.BlockedLabels = blockedLabels
m.filter = iradix.New()
for _, prefix := range m.AllowedPrefixes {
m.filter, _, _ = m.filter.Insert([]byte(prefix), true)
}
for _, prefix := range m.BlockedPrefixes {
m.filter, _, _ = m.filter.Insert([]byte(prefix), false)
}
}
// labelIsAllowed return true if a should be included in metric
// the caller should lock m.filterLock while calling this method
func (m *Metrics) labelIsAllowed(label *Label) bool {
labelName := (*label).Name
if m.blockedLabels != nil {
_, ok := m.blockedLabels[labelName]
if ok {
// If present, let's remove this label
return false
}
}
if m.allowedLabels != nil {
_, ok := m.allowedLabels[labelName]
return ok
}
// Allow by default
return true
}
// filterLabels return only allowed labels
// the caller should lock m.filterLock while calling this method
func (m *Metrics) filterLabels(labels []Label) []Label {
if labels == nil {
return nil
}
toReturn := []Label{}
for _, label := range labels {
if m.labelIsAllowed(&label) {
toReturn = append(toReturn, label)
}
}
return toReturn
}
// Returns whether the metric should be allowed based on configured prefix filters
// Also return the applicable labels
func (m *Metrics) allowMetric(key []string, labels []Label) (bool, []Label) {
m.filterLock.RLock()
defer m.filterLock.RUnlock()
if m.filter == nil || m.filter.Len() == 0 {
return m.Config.FilterDefault, m.filterLabels(labels)
}
_, allowed, ok := m.filter.Root().LongestPrefix([]byte(strings.Join(key, ".")))
if !ok {
return m.Config.FilterDefault, m.filterLabels(labels)
}
return allowed.(bool), m.filterLabels(labels)
}
// Periodically collects runtime stats to publish
func (m *Metrics) collectStats() {
for {
time.Sleep(m.ProfileInterval)
m.emitRuntimeStats()
}
}
// Emits various runtime statsitics
func (m *Metrics) emitRuntimeStats() {
// Export number of Goroutines
numRoutines := runtime.NumGoroutine()
m.SetGauge([]string{"runtime", "num_goroutines"}, float32(numRoutines))
// Export memory stats
var stats runtime.MemStats
runtime.ReadMemStats(&stats)
m.SetGauge([]string{"runtime", "alloc_bytes"}, float32(stats.Alloc))
m.SetGauge([]string{"runtime", "sys_bytes"}, float32(stats.Sys))
m.SetGauge([]string{"runtime", "malloc_count"}, float32(stats.Mallocs))
m.SetGauge([]string{"runtime", "free_count"}, float32(stats.Frees))
m.SetGauge([]string{"runtime", "heap_objects"}, float32(stats.HeapObjects))
m.SetGauge([]string{"runtime", "total_gc_pause_ns"}, float32(stats.PauseTotalNs))
m.SetGauge([]string{"runtime", "total_gc_runs"}, float32(stats.NumGC))
// Export info about the last few GC runs
num := stats.NumGC
// Handle wrap around
if num < m.lastNumGC {
m.lastNumGC = 0
}
// Ensure we don't scan more than 256
if num-m.lastNumGC >= 256 {
m.lastNumGC = num - 255
}
for i := m.lastNumGC; i < num; i++ {
pause := stats.PauseNs[i%256]
m.AddSample([]string{"runtime", "gc_pause_ns"}, float32(pause))
}
m.lastNumGC = num
}
// Creates a new slice with the provided string value as the first element
// and the provided slice values as the remaining values.
// Ordering of the values in the provided input slice is kept in tact in the output slice.
func insert(i int, v string, s []string) []string {
// Allocate new slice to avoid modifying the input slice
newS := make([]string, len(s)+1)
// Copy s[0, i-1] into newS
for j := 0; j < i; j++ {
newS[j] = s[j]
}
// Insert provided element at index i
newS[i] = v
// Copy s[i, len(s)-1] into newS starting at newS[i+1]
for j := i; j < len(s); j++ {
newS[j+1] = s[j]
}
return newS
}