github.com/openethereum/go-ethereum@v1.9.7/metrics/metrics_test.go (about)

     1  package metrics
     2  
     3  import (
     4  	"fmt"
     5  	"io/ioutil"
     6  	"log"
     7  	"sync"
     8  	"testing"
     9  	"time"
    10  )
    11  
    12  const FANOUT = 128
    13  
    14  // Stop the compiler from complaining during debugging.
    15  var (
    16  	_ = ioutil.Discard
    17  	_ = log.LstdFlags
    18  )
    19  
    20  func BenchmarkMetrics(b *testing.B) {
    21  	r := NewRegistry()
    22  	c := NewRegisteredCounter("counter", r)
    23  	g := NewRegisteredGauge("gauge", r)
    24  	gf := NewRegisteredGaugeFloat64("gaugefloat64", r)
    25  	h := NewRegisteredHistogram("histogram", r, NewUniformSample(100))
    26  	m := NewRegisteredMeter("meter", r)
    27  	t := NewRegisteredTimer("timer", r)
    28  	RegisterDebugGCStats(r)
    29  	RegisterRuntimeMemStats(r)
    30  	b.ResetTimer()
    31  	ch := make(chan bool)
    32  
    33  	wgD := &sync.WaitGroup{}
    34  	/*
    35  		wgD.Add(1)
    36  		go func() {
    37  			defer wgD.Done()
    38  			//log.Println("go CaptureDebugGCStats")
    39  			for {
    40  				select {
    41  				case <-ch:
    42  					//log.Println("done CaptureDebugGCStats")
    43  					return
    44  				default:
    45  					CaptureDebugGCStatsOnce(r)
    46  				}
    47  			}
    48  		}()
    49  	//*/
    50  
    51  	wgR := &sync.WaitGroup{}
    52  	//*
    53  	wgR.Add(1)
    54  	go func() {
    55  		defer wgR.Done()
    56  		//log.Println("go CaptureRuntimeMemStats")
    57  		for {
    58  			select {
    59  			case <-ch:
    60  				//log.Println("done CaptureRuntimeMemStats")
    61  				return
    62  			default:
    63  				CaptureRuntimeMemStatsOnce(r)
    64  			}
    65  		}
    66  	}()
    67  	//*/
    68  
    69  	wgW := &sync.WaitGroup{}
    70  	/*
    71  		wgW.Add(1)
    72  		go func() {
    73  			defer wgW.Done()
    74  			//log.Println("go Write")
    75  			for {
    76  				select {
    77  				case <-ch:
    78  					//log.Println("done Write")
    79  					return
    80  				default:
    81  					WriteOnce(r, ioutil.Discard)
    82  				}
    83  			}
    84  		}()
    85  	//*/
    86  
    87  	wg := &sync.WaitGroup{}
    88  	wg.Add(FANOUT)
    89  	for i := 0; i < FANOUT; i++ {
    90  		go func(i int) {
    91  			defer wg.Done()
    92  			//log.Println("go", i)
    93  			for i := 0; i < b.N; i++ {
    94  				c.Inc(1)
    95  				g.Update(int64(i))
    96  				gf.Update(float64(i))
    97  				h.Update(int64(i))
    98  				m.Mark(1)
    99  				t.Update(1)
   100  			}
   101  			//log.Println("done", i)
   102  		}(i)
   103  	}
   104  	wg.Wait()
   105  	close(ch)
   106  	wgD.Wait()
   107  	wgR.Wait()
   108  	wgW.Wait()
   109  }
   110  
   111  func Example() {
   112  	c := NewCounter()
   113  	Register("money", c)
   114  	c.Inc(17)
   115  
   116  	// Threadsafe registration
   117  	t := GetOrRegisterTimer("db.get.latency", nil)
   118  	t.Time(func() { time.Sleep(10 * time.Millisecond) })
   119  	t.Update(1)
   120  
   121  	fmt.Println(c.Count())
   122  	fmt.Println(t.Min())
   123  	// Output: 17
   124  	// 1
   125  }