From: Dmitriy Vyukov <dvyukov@google.com>
Date: Wed, 27 Jun 2012 17:57:49 +0000 (+0400)
Subject: runtime: add goroutine creation benchmark
X-Git-Tag: go1.1rc2~2868
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=5a5e698c8fceec38c34f86375dcd44fb1a7a8939;p=gostls13.git

runtime: add goroutine creation benchmark
Current results on 2 core darwin/amd64:
BenchmarkGoroutineChain		351 ns/op
BenchmarkGoroutineChain-2	3840 ns/op
BenchmarkGoroutineChain-4	4040 ns/op
BenchmarkConcGoroutineChain	350 ns/op
BenchmarkConcGoroutineChain-2	875 ns/op
BenchmarkConcGoroutineChain-4	2027 ns/op

R=r, rsc
CC=golang-dev
https://golang.org/cl/6332054
---

diff --git a/src/pkg/runtime/proc_test.go b/src/pkg/runtime/proc_test.go
index 32111080a5..1d51c5271e 100644
--- a/src/pkg/runtime/proc_test.go
+++ b/src/pkg/runtime/proc_test.go
@@ -123,3 +123,29 @@ func BenchmarkSyscallWork(b *testing.B) {
 		<-c
 	}
 }
+
+func BenchmarkCreateGoroutines(b *testing.B) {
+	benchmarkCreateGoroutines(b, 1)
+}
+
+func BenchmarkCreateGoroutinesParallel(b *testing.B) {
+	benchmarkCreateGoroutines(b, runtime.GOMAXPROCS(-1))
+}
+
+func benchmarkCreateGoroutines(b *testing.B, procs int) {
+	c := make(chan bool)
+	var f func(n int)
+	f = func(n int) {
+		if n == 0 {
+			c <- true
+			return
+		}
+		go f(n - 1)
+	}
+	for i := 0; i < procs; i++ {
+		go f(b.N / procs)
+	}
+	for i := 0; i < procs; i++ {
+		<-c
+	}
+}