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path: root/src/pkg/runtime/chan_test.go
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-rw-r--r--src/pkg/runtime/chan_test.go267
1 files changed, 267 insertions, 0 deletions
diff --git a/src/pkg/runtime/chan_test.go b/src/pkg/runtime/chan_test.go
new file mode 100644
index 000000000..c5ffe93ac
--- /dev/null
+++ b/src/pkg/runtime/chan_test.go
@@ -0,0 +1,267 @@
+// Copyright 2009 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/atomic"
+ "testing"
+)
+
+func TestChanSendInterface(t *testing.T) {
+ type mt struct{}
+ m := &mt{}
+ c := make(chan interface{}, 1)
+ c <- m
+ select {
+ case c <- m:
+ default:
+ }
+ select {
+ case c <- m:
+ case c <- &mt{}:
+ default:
+ }
+}
+
+func BenchmarkSelectUncontended(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ c := make(chan bool, procs)
+ for p := 0; p < procs; p++ {
+ go func() {
+ myc1 := make(chan int, 1)
+ myc2 := make(chan int, 1)
+ myc1 <- 0
+ for atomic.AddInt32(&N, -1) >= 0 {
+ for g := 0; g < CallsPerSched; g++ {
+ select {
+ case <-myc1:
+ myc2 <- 0
+ case <-myc2:
+ myc1 <- 0
+ }
+ }
+ }
+ c <- true
+ }()
+ }
+ for p := 0; p < procs; p++ {
+ <-c
+ }
+}
+
+func BenchmarkSelectContended(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ c := make(chan bool, procs)
+ myc1 := make(chan int, procs)
+ myc2 := make(chan int, procs)
+ for p := 0; p < procs; p++ {
+ myc1 <- 0
+ go func() {
+ for atomic.AddInt32(&N, -1) >= 0 {
+ for g := 0; g < CallsPerSched; g++ {
+ select {
+ case <-myc1:
+ myc2 <- 0
+ case <-myc2:
+ myc1 <- 0
+ }
+ }
+ }
+ c <- true
+ }()
+ }
+ for p := 0; p < procs; p++ {
+ <-c
+ }
+}
+
+func BenchmarkSelectNonblock(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ c := make(chan bool, procs)
+ for p := 0; p < procs; p++ {
+ go func() {
+ myc1 := make(chan int)
+ myc2 := make(chan int)
+ myc3 := make(chan int, 1)
+ myc4 := make(chan int, 1)
+ for atomic.AddInt32(&N, -1) >= 0 {
+ for g := 0; g < CallsPerSched; g++ {
+ select {
+ case <-myc1:
+ default:
+ }
+ select {
+ case myc2 <- 0:
+ default:
+ }
+ select {
+ case <-myc3:
+ default:
+ }
+ select {
+ case myc4 <- 0:
+ default:
+ }
+ }
+ }
+ c <- true
+ }()
+ }
+ for p := 0; p < procs; p++ {
+ <-c
+ }
+}
+
+func BenchmarkChanUncontended(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ c := make(chan bool, procs)
+ for p := 0; p < procs; p++ {
+ go func() {
+ myc := make(chan int, CallsPerSched)
+ for atomic.AddInt32(&N, -1) >= 0 {
+ for g := 0; g < CallsPerSched; g++ {
+ myc <- 0
+ }
+ for g := 0; g < CallsPerSched; g++ {
+ <-myc
+ }
+ }
+ c <- true
+ }()
+ }
+ for p := 0; p < procs; p++ {
+ <-c
+ }
+}
+
+func BenchmarkChanContended(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ c := make(chan bool, procs)
+ myc := make(chan int, procs*CallsPerSched)
+ for p := 0; p < procs; p++ {
+ go func() {
+ for atomic.AddInt32(&N, -1) >= 0 {
+ for g := 0; g < CallsPerSched; g++ {
+ myc <- 0
+ }
+ for g := 0; g < CallsPerSched; g++ {
+ <-myc
+ }
+ }
+ c <- true
+ }()
+ }
+ for p := 0; p < procs; p++ {
+ <-c
+ }
+}
+
+func BenchmarkChanSync(b *testing.B) {
+ const CallsPerSched = 1000
+ procs := 2
+ N := int32(b.N / CallsPerSched / procs * procs)
+ c := make(chan bool, procs)
+ myc := make(chan int)
+ for p := 0; p < procs; p++ {
+ go func() {
+ for {
+ i := atomic.AddInt32(&N, -1)
+ if i < 0 {
+ break
+ }
+ for g := 0; g < CallsPerSched; g++ {
+ if i%2 == 0 {
+ <-myc
+ myc <- 0
+ } else {
+ myc <- 0
+ <-myc
+ }
+ }
+ }
+ c <- true
+ }()
+ }
+ for p := 0; p < procs; p++ {
+ <-c
+ }
+}
+
+func benchmarkChanProdCons(b *testing.B, chanSize, localWork int) {
+ const CallsPerSched = 1000
+ procs := runtime.GOMAXPROCS(-1)
+ N := int32(b.N / CallsPerSched)
+ c := make(chan bool, 2*procs)
+ myc := make(chan int, chanSize)
+ for p := 0; p < procs; p++ {
+ go func() {
+ foo := 0
+ for atomic.AddInt32(&N, -1) >= 0 {
+ for g := 0; g < CallsPerSched; g++ {
+ for i := 0; i < localWork; i++ {
+ foo *= 2
+ foo /= 2
+ }
+ myc <- 1
+ }
+ }
+ myc <- 0
+ c <- foo == 42
+ }()
+ go func() {
+ foo := 0
+ for {
+ v := <-myc
+ if v == 0 {
+ break
+ }
+ for i := 0; i < localWork; i++ {
+ foo *= 2
+ foo /= 2
+ }
+ }
+ c <- foo == 42
+ }()
+ }
+ for p := 0; p < procs; p++ {
+ <-c
+ <-c
+ }
+}
+
+func BenchmarkChanProdCons0(b *testing.B) {
+ benchmarkChanProdCons(b, 0, 0)
+}
+
+func BenchmarkChanProdCons10(b *testing.B) {
+ benchmarkChanProdCons(b, 10, 0)
+}
+
+func BenchmarkChanProdCons100(b *testing.B) {
+ benchmarkChanProdCons(b, 100, 0)
+}
+
+func BenchmarkChanProdConsWork0(b *testing.B) {
+ benchmarkChanProdCons(b, 0, 100)
+}
+
+func BenchmarkChanProdConsWork10(b *testing.B) {
+ benchmarkChanProdCons(b, 10, 100)
+}
+
+func BenchmarkChanProdConsWork100(b *testing.B) {
+ benchmarkChanProdCons(b, 100, 100)
+}