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package metrics
import (
"runtime"
"runtime/debug"
"testing"
"time"
)
func BenchmarkDebugGCStats(b *testing.B) {
r := NewRegistry()
RegisterDebugGCStats(r)
b.ResetTimer()
for i := 0; i < b.N; i++ {
CaptureDebugGCStatsOnce(r)
}
}
func TestDebugGCStatsBlocking(t *testing.T) {
if g := runtime.GOMAXPROCS(0); g < 2 {
t.Skipf("skipping TestDebugGCMemStatsBlocking with GOMAXPROCS=%d\n", g)
return
}
ch := make(chan int)
go testDebugGCStatsBlocking(ch)
var gcStats debug.GCStats
t0 := time.Now()
debug.ReadGCStats(&gcStats)
t1 := time.Now()
t.Log("i++ during debug.ReadGCStats:", <-ch)
go testDebugGCStatsBlocking(ch)
d := t1.Sub(t0)
t.Log(d)
time.Sleep(d)
t.Log("i++ during time.Sleep:", <-ch)
}
func testDebugGCStatsBlocking(ch chan int) {
i := 0
for {
select {
case ch <- i:
return
default:
i++
}
}
}