Add benchmarks for commonly used routines.

R=rsc, r, r1
https://golang.org/cl/160046

src/pkg/fmt/fmt_test.go

@@ -250,6 +250,24 @@ func TestSprintf(t *testing.T) {
 	}
 }
 
+func BenchmarkSprintfEmpty(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Sprintf("")
+	}
+}
+
+func BenchmarkSprintfString(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Sprintf("%s", "hello")
+	}
+}
+
+func BenchmarkSprintfInt(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Sprintf("%d", 5)
+	}
+}
+
 type flagPrinter struct{}
 
 func (*flagPrinter) Format(f State, c int) {

src/pkg/hash/crc32/crc32_test.go

@@ -60,3 +60,17 @@ func TestGolden(t *testing.T) {
 		}
 	}
 }
+
+func BenchmarkCrc32KB(b *testing.B) {
+	b.StopTimer();
+	data := make([]uint8, 1024);
+	for i := 0; i < 1024; i++ {
+		data[i] = uint8(i)
+	}
+	c := NewIEEE();
+	b.StartTimer();
+
+	for i := 0; i < b.N; i++ {
+		c.Write(data)
+	}
+}

src/pkg/sort/sort_test.go

@@ -7,6 +7,7 @@ package sort
 import (
 	"fmt";
 	"rand";
+	"strconv";
 	"testing";
 )
 
@@ -86,6 +87,45 @@ func TestSortLarge_Random(t *testing.T) {
 	}
 }
 
+func BenchmarkSortString1K(b *testing.B) {
+	b.StopTimer();
+	for i := 0; i < b.N; i++ {
+		data := make([]string, 1<<10);
+		for i := 0; i < len(data); i++ {
+			data[i] = strconv.Itoa(i ^ 0x2cc)
+		}
+		b.StartTimer();
+		SortStrings(data);
+		b.StopTimer();
+	}
+}
+
+func BenchmarkSortInt1K(b *testing.B) {
+	b.StopTimer();
+	for i := 0; i < b.N; i++ {
+		data := make([]int, 1<<10);
+		for i := 0; i < len(data); i++ {
+			data[i] = i ^ 0x2cc
+		}
+		b.StartTimer();
+		SortInts(data);
+		b.StopTimer();
+	}
+}
+
+func BenchmarkSortInt64K(b *testing.B) {
+	b.StopTimer();
+	for i := 0; i < b.N; i++ {
+		data := make([]int, 1<<16);
+		for i := 0; i < len(data); i++ {
+			data[i] = i ^ 0xcccc
+		}
+		b.StartTimer();
+		SortInts(data);
+		b.StopTimer();
+	}
+}
+
 const (
 	_Sawtooth	= iota;
 	_Rand;

src/pkg/strconv/atof_test.go

@@ -138,3 +138,27 @@ func testAtof(t *testing.T, opt bool) {
 func TestAtof(t *testing.T)	{ testAtof(t, true) }
 
 func TestAtofSlow(t *testing.T)	{ testAtof(t, false) }
+
+func BenchmarkAtofDecimal(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atof("33909")
+	}
+}
+
+func BenchmarkAtofFloat(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atof("339.7784")
+	}
+}
+
+func BenchmarkAtofFloatExp(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atof("-5.09e75")
+	}
+}
+
+func BenchmarkAtofBig(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atof("123456789123456789123456789")
+	}
+}

src/pkg/strconv/atoi_test.go

@@ -277,3 +277,27 @@ func TestAtoi(t *testing.T) {
 		}
 	}
 }
+
+func BenchmarkAtoi(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atoi("12345678")
+	}
+}
+
+func BenchmarkAtoiNeg(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atoi("-12345678")
+	}
+}
+
+func BenchmarkAtoi64(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atoi64("12345678901234")
+	}
+}
+
+func BenchmarkAtoi64Neg(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Atoi64("-12345678901234")
+	}
+}

src/pkg/sync/mutex_test.go

@@ -12,8 +12,8 @@ import (
 	"testing";
 )
 
-func HammerSemaphore(s *uint32, cdone chan bool) {
-	for i := 0; i < 1000; i++ {
+func HammerSemaphore(s *uint32, loops int, cdone chan bool) {
+	for i := 0; i < loops; i++ {
 		runtime.Semacquire(s);
 		runtime.Semrelease(s);
 	}
@@ -25,16 +25,36 @@ func TestSemaphore(t *testing.T) {
 	*s = 1;
 	c := make(chan bool);
 	for i := 0; i < 10; i++ {
-		go HammerSemaphore(s, c)
+		go HammerSemaphore(s, 1000, c)
 	}
 	for i := 0; i < 10; i++ {
 		<-c
 	}
 }
 
+func BenchmarkUncontendedSemaphore(b *testing.B) {
+	s := new(uint32);
+	*s = 1;
+	HammerSemaphore(s, b.N, make(chan bool, 2));
+}
+
+func BenchmarkContendedSemaphore(b *testing.B) {
+	b.StopTimer();
+	s := new(uint32);
+	*s = 1;
+	c := make(chan bool);
+	runtime.GOMAXPROCS(2);
+	b.StartTimer();
+
+	go HammerSemaphore(s, b.N/2, c);
+	go HammerSemaphore(s, b.N/2, c);
+	<-c;
+	<-c;
+}
 
-func HammerMutex(m *Mutex, cdone chan bool) {
-	for i := 0; i < 1000; i++ {
+
+func HammerMutex(m *Mutex, loops int, cdone chan bool) {
+	for i := 0; i < loops; i++ {
 		m.Lock();
 		m.Unlock();
 	}
@@ -45,9 +65,27 @@ func TestMutex(t *testing.T) {
 	m := new(Mutex);
 	c := make(chan bool);
 	for i := 0; i < 10; i++ {
-		go HammerMutex(m, c)
+		go HammerMutex(m, 1000, c)
 	}
 	for i := 0; i < 10; i++ {
 		<-c
 	}
 }
+
+func BenchmarkUncontendedMutex(b *testing.B) {
+	m := new(Mutex);
+	HammerMutex(m, b.N, make(chan bool, 2));
+}
+
+func BenchmarkContendedMutex(b *testing.B) {
+	b.StopTimer();
+	m := new(Mutex);
+	c := make(chan bool);
+	runtime.GOMAXPROCS(2);
+	b.StartTimer();
+
+	go HammerMutex(m, b.N/2, c);
+	go HammerMutex(m, b.N/2, c);
+	<-c;
+	<-c;
+}

src/pkg/time/time_test.go

@@ -82,3 +82,15 @@ func TestSecondsToLocalTime(t *testing.T) {
 		}
 	}
 }
+
+func BenchmarkSeconds(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Seconds()
+	}
+}
+
+func BenchmarkNanoseconds(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Nanoseconds()
+	}
+}