plugeth/metrics/runtime_test.go
2019-11-22 16:04:35 +01:00

89 lines
2.0 KiB
Go

package metrics
import (
"runtime"
"testing"
"time"
)
func BenchmarkRuntimeMemStats(b *testing.B) {
r := NewRegistry()
RegisterRuntimeMemStats(r)
b.ResetTimer()
for i := 0; i < b.N; i++ {
CaptureRuntimeMemStatsOnce(r)
}
}
func TestRuntimeMemStats(t *testing.T) {
r := NewRegistry()
RegisterRuntimeMemStats(r)
CaptureRuntimeMemStatsOnce(r)
zero := runtimeMetrics.MemStats.PauseNs.Count() // Get a "zero" since GC may have run before these tests.
runtime.GC()
CaptureRuntimeMemStatsOnce(r)
if count := runtimeMetrics.MemStats.PauseNs.Count(); count-zero != 1 {
t.Fatal(count - zero)
}
runtime.GC()
runtime.GC()
CaptureRuntimeMemStatsOnce(r)
if count := runtimeMetrics.MemStats.PauseNs.Count(); count-zero != 3 {
t.Fatal(count - zero)
}
for i := 0; i < 256; i++ {
runtime.GC()
}
CaptureRuntimeMemStatsOnce(r)
if count := runtimeMetrics.MemStats.PauseNs.Count(); count-zero != 259 {
t.Fatal(count - zero)
}
for i := 0; i < 257; i++ {
runtime.GC()
}
CaptureRuntimeMemStatsOnce(r)
if count := runtimeMetrics.MemStats.PauseNs.Count(); count-zero != 515 { // We lost one because there were too many GCs between captures.
t.Fatal(count - zero)
}
}
func TestRuntimeMemStatsNumThread(t *testing.T) {
r := NewRegistry()
RegisterRuntimeMemStats(r)
CaptureRuntimeMemStatsOnce(r)
if value := runtimeMetrics.NumThread.Value(); value < 1 {
t.Fatalf("got NumThread: %d, wanted at least 1", value)
}
}
func TestRuntimeMemStatsBlocking(t *testing.T) {
if g := runtime.GOMAXPROCS(0); g < 2 {
t.Skipf("skipping TestRuntimeMemStatsBlocking with GOMAXPROCS=%d\n", g)
}
ch := make(chan int)
go testRuntimeMemStatsBlocking(ch)
var memStats runtime.MemStats
t0 := time.Now()
runtime.ReadMemStats(&memStats)
t1 := time.Now()
t.Log("i++ during runtime.ReadMemStats:", <-ch)
go testRuntimeMemStatsBlocking(ch)
d := t1.Sub(t0)
t.Log(d)
time.Sleep(d)
t.Log("i++ during time.Sleep:", <-ch)
}
func testRuntimeMemStatsBlocking(ch chan int) {
i := 0
for {
select {
case ch <- i:
return
default:
i++
}
}
}