gitlab.com/aquachain/aquachain@v1.17.16-rc3.0.20221018032414-e3ddf1e1c055/common/metrics/debug.go (about)

     1  // Copyright 2018 The aquachain Authors
     2  // This file is part of the aquachain library.
     3  //
     4  // The aquachain library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The aquachain library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the aquachain library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package metrics
    18  
    19  import (
    20  	"runtime/debug"
    21  	"time"
    22  )
    23  
    24  var (
    25  	debugMetrics struct {
    26  		GCStats struct {
    27  			LastGC Gauge
    28  			NumGC  Gauge
    29  			Pause  Histogram
    30  			//PauseQuantiles Histogram
    31  			PauseTotal Gauge
    32  		}
    33  		ReadGCStats Timer
    34  	}
    35  	gcStats debug.GCStats
    36  )
    37  
    38  // Capture new values for the Go garbage collector statistics exported in
    39  // debug.GCStats.  This is designed to be called as a goroutine.
    40  func CaptureDebugGCStats(r Registry, d time.Duration) {
    41  	for range time.Tick(d) {
    42  		CaptureDebugGCStatsOnce(r)
    43  	}
    44  }
    45  
    46  // Capture new values for the Go garbage collector statistics exported in
    47  // debug.GCStats.  This is designed to be called in a background goroutine.
    48  // Giving a registry which has not been given to RegisterDebugGCStats will
    49  // panic.
    50  //
    51  // Be careful (but much less so) with this because debug.ReadGCStats calls
    52  // the C function runtime·lock(runtime·mheap) which, while not a stop-the-world
    53  // operation, isn't something you want to be doing all the time.
    54  func CaptureDebugGCStatsOnce(r Registry) {
    55  	lastGC := gcStats.LastGC
    56  	t := time.Now()
    57  	debug.ReadGCStats(&gcStats)
    58  	debugMetrics.ReadGCStats.UpdateSince(t)
    59  
    60  	debugMetrics.GCStats.LastGC.Update(gcStats.LastGC.UnixNano())
    61  	debugMetrics.GCStats.NumGC.Update(gcStats.NumGC)
    62  	if lastGC != gcStats.LastGC && 0 < len(gcStats.Pause) {
    63  		debugMetrics.GCStats.Pause.Update(int64(gcStats.Pause[0]))
    64  	}
    65  	//debugMetrics.GCStats.PauseQuantiles.Update(gcStats.PauseQuantiles)
    66  	debugMetrics.GCStats.PauseTotal.Update(int64(gcStats.PauseTotal))
    67  }
    68  
    69  // Register metrics for the Go garbage collector statistics exported in
    70  // debug.GCStats.  The metrics are named by their fully-qualified Go symbols,
    71  // i.e. debug.GCStats.PauseTotal.
    72  func RegisterDebugGCStats(r Registry) {
    73  	debugMetrics.GCStats.LastGC = NewGauge()
    74  	debugMetrics.GCStats.NumGC = NewGauge()
    75  	debugMetrics.GCStats.Pause = NewHistogram(NewExpDecaySample(1028, 0.015))
    76  	//debugMetrics.GCStats.PauseQuantiles = NewHistogram(NewExpDecaySample(1028, 0.015))
    77  	debugMetrics.GCStats.PauseTotal = NewGauge()
    78  	debugMetrics.ReadGCStats = NewTimer()
    79  
    80  	r.Register("debug.GCStats.LastGC", debugMetrics.GCStats.LastGC)
    81  	r.Register("debug.GCStats.NumGC", debugMetrics.GCStats.NumGC)
    82  	r.Register("debug.GCStats.Pause", debugMetrics.GCStats.Pause)
    83  	//r.Register("debug.GCStats.PauseQuantiles", debugMetrics.GCStats.PauseQuantiles)
    84  	r.Register("debug.GCStats.PauseTotal", debugMetrics.GCStats.PauseTotal)
    85  	r.Register("debug.ReadGCStats", debugMetrics.ReadGCStats)
    86  }
    87  
    88  // Allocate an initial slice for gcStats.Pause to avoid allocations during
    89  // normal operation.
    90  func init() {
    91  	gcStats.Pause = make([]time.Duration, 11)
    92  }