VOL-2496 Add "event listen" command to voltctl
Change-Id: I8f1fb34b55f56c8125142ac289e2f19fc170d804
diff --git a/vendor/github.com/rcrowley/go-metrics/debug.go b/vendor/github.com/rcrowley/go-metrics/debug.go
new file mode 100644
index 0000000..043ccef
--- /dev/null
+++ b/vendor/github.com/rcrowley/go-metrics/debug.go
@@ -0,0 +1,76 @@
+package metrics
+
+import (
+ "runtime/debug"
+ "time"
+)
+
+var (
+ debugMetrics struct {
+ GCStats struct {
+ LastGC Gauge
+ NumGC Gauge
+ Pause Histogram
+ //PauseQuantiles Histogram
+ PauseTotal Gauge
+ }
+ ReadGCStats Timer
+ }
+ gcStats debug.GCStats
+)
+
+// Capture new values for the Go garbage collector statistics exported in
+// debug.GCStats. This is designed to be called as a goroutine.
+func CaptureDebugGCStats(r Registry, d time.Duration) {
+ for _ = range time.Tick(d) {
+ CaptureDebugGCStatsOnce(r)
+ }
+}
+
+// Capture new values for the Go garbage collector statistics exported in
+// debug.GCStats. This is designed to be called in a background goroutine.
+// Giving a registry which has not been given to RegisterDebugGCStats will
+// panic.
+//
+// Be careful (but much less so) with this because debug.ReadGCStats calls
+// the C function runtime·lock(runtime·mheap) which, while not a stop-the-world
+// operation, isn't something you want to be doing all the time.
+func CaptureDebugGCStatsOnce(r Registry) {
+ lastGC := gcStats.LastGC
+ t := time.Now()
+ debug.ReadGCStats(&gcStats)
+ debugMetrics.ReadGCStats.UpdateSince(t)
+
+ debugMetrics.GCStats.LastGC.Update(int64(gcStats.LastGC.UnixNano()))
+ debugMetrics.GCStats.NumGC.Update(int64(gcStats.NumGC))
+ if lastGC != gcStats.LastGC && 0 < len(gcStats.Pause) {
+ debugMetrics.GCStats.Pause.Update(int64(gcStats.Pause[0]))
+ }
+ //debugMetrics.GCStats.PauseQuantiles.Update(gcStats.PauseQuantiles)
+ debugMetrics.GCStats.PauseTotal.Update(int64(gcStats.PauseTotal))
+}
+
+// Register metrics for the Go garbage collector statistics exported in
+// debug.GCStats. The metrics are named by their fully-qualified Go symbols,
+// i.e. debug.GCStats.PauseTotal.
+func RegisterDebugGCStats(r Registry) {
+ debugMetrics.GCStats.LastGC = NewGauge()
+ debugMetrics.GCStats.NumGC = NewGauge()
+ debugMetrics.GCStats.Pause = NewHistogram(NewExpDecaySample(1028, 0.015))
+ //debugMetrics.GCStats.PauseQuantiles = NewHistogram(NewExpDecaySample(1028, 0.015))
+ debugMetrics.GCStats.PauseTotal = NewGauge()
+ debugMetrics.ReadGCStats = NewTimer()
+
+ r.Register("debug.GCStats.LastGC", debugMetrics.GCStats.LastGC)
+ r.Register("debug.GCStats.NumGC", debugMetrics.GCStats.NumGC)
+ r.Register("debug.GCStats.Pause", debugMetrics.GCStats.Pause)
+ //r.Register("debug.GCStats.PauseQuantiles", debugMetrics.GCStats.PauseQuantiles)
+ r.Register("debug.GCStats.PauseTotal", debugMetrics.GCStats.PauseTotal)
+ r.Register("debug.ReadGCStats", debugMetrics.ReadGCStats)
+}
+
+// Allocate an initial slice for gcStats.Pause to avoid allocations during
+// normal operation.
+func init() {
+ gcStats.Pause = make([]time.Duration, 11)
+}