runtime: faster finalizers
Linux/amd64, 2 x Intel Xeon E5620, 8 HT cores, 2.40GHz
benchmark old ns/op new ns/op delta
BenchmarkFinalizer 420.00 261.00 -37.86%
BenchmarkFinalizer-2 985.00 201.00 -79.59%
BenchmarkFinalizer-4 1077.00 244.00 -77.34%
BenchmarkFinalizer-8 1155.00 180.00 -84.42%
BenchmarkFinalizer-16 1182.00 184.00 -84.43%
BenchmarkFinalizerRun 2128.00 1378.00 -35.24%
BenchmarkFinalizerRun-2 1655.00 1418.00 -14.32%
BenchmarkFinalizerRun-4 1634.00 1522.00 -6.85%
BenchmarkFinalizerRun-8 2213.00 1581.00 -28.56%
BenchmarkFinalizerRun-16 2424.00 1599.00 -34.03%
Darwin/amd64, Intel L9600, 2 cores, 2.13GHz
benchmark old ns/op new ns/op delta
BenchmarkChanCreation 1451.00 926.00 -36.18%
BenchmarkChanCreation-2 3124.00 1412.00 -54.80%
BenchmarkChanCreation-4 6121.00 2628.00 -57.07%
BenchmarkFinalizer 684.00 420.00 -38.60%
BenchmarkFinalizer-2 11195.00 398.00 -96.44%
BenchmarkFinalizer-4 15862.00 654.00 -95.88%
BenchmarkFinalizerRun 2025.00 1397.00 -31.01%
BenchmarkFinalizerRun-2 3920.00 1447.00 -63.09%
BenchmarkFinalizerRun-4 9471.00 1545.00 -83.69%
R=golang-dev, cw, rsc
CC=golang-dev
https://golang.org/cl/4963057
diff --git a/src/pkg/runtime/mfinal_test.go b/src/pkg/runtime/mfinal_test.go
new file mode 100644
index 0000000..de63271
--- /dev/null
+++ b/src/pkg/runtime/mfinal_test.go
@@ -0,0 +1,64 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime_test
+
+import (
+ "runtime"
+ "sync"
+ "sync/atomic"
+ "testing"
+)
+
+func fin(v *int) {
+}
+
+func BenchmarkFinalizer(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ var wg sync.WaitGroup
+ wg.Add(procs)
+ for p := 0; p < procs; p++ {
+ go func() {
+ var data [CallsPerSched]*int
+ for i := 0; i < CallsPerSched; i++ {
+ data[i] = new(int)
+ }
+ for atomic.AddInt32(&N, -1) >= 0 {
+ runtime.Gosched()
+ for i := 0; i < CallsPerSched; i++ {
+ runtime.SetFinalizer(data[i], fin)
+ }
+ for i := 0; i < CallsPerSched; i++ {
+ runtime.SetFinalizer(data[i], nil)
+ }
+ }
+ wg.Done()
+ }()
+ }
+ wg.Wait()
+}
+
+func BenchmarkFinalizerRun(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ var wg sync.WaitGroup
+ wg.Add(procs)
+ for p := 0; p < procs; p++ {
+ go func() {
+ for atomic.AddInt32(&N, -1) >= 0 {
+ runtime.Gosched()
+ for i := 0; i < CallsPerSched; i++ {
+ v := new(int)
+ runtime.SetFinalizer(v, fin)
+ }
+ runtime.GC()
+ }
+ wg.Done()
+ }()
+ }
+ wg.Wait()
+}
