test/bench/garbage: fix parser benchmark

+add standard bench output to tree2
+print GOMAXPROCS as go test does

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5992044

test/bench/garbage/parser.go

@@ -195,7 +195,6 @@ var packages = []string{
 	"mime",
 	"net",
 	"os",
-	"exp/signal",
 	"path",
 	"math/rand",
 	"reflect",
@@ -215,7 +214,6 @@ var packages = []string{
 	"testing",
 	"testing/iotest",
 	"testing/quick",
-	"testing/script",
 	"time",
 	"unicode",
 	"unicode/utf8",

test/bench/garbage/stats.go

@@ -14,16 +14,21 @@ import (
 func gcstats(name string, n int, t time.Duration) {
 	st := new(runtime.MemStats)
 	runtime.ReadMemStats(st)
-	fmt.Printf("garbage.%sMem Alloc=%d/%d Heap=%d NextGC=%d Mallocs=%d\n", name, st.Alloc, st.TotalAlloc, st.Sys, st.NextGC, st.Mallocs)
+	nprocs := runtime.GOMAXPROCS(-1)
-	fmt.Printf("garbage.%s %d %d ns/op\n", name, n, t.Nanoseconds()/int64(n))
+	cpus := ""
-	fmt.Printf("garbage.%sLastPause 1 %d ns/op\n", name, st.PauseNs[(st.NumGC-1)%uint32(len(st.PauseNs))])
+	if nprocs != 1 {
-	fmt.Printf("garbage.%sPause %d %d ns/op\n", name, st.NumGC, int64(st.PauseTotalNs)/int64(st.NumGC))
+		cpus = fmt.Sprintf("-%d", nprocs)
+	}
+	fmt.Printf("garbage.%sMem%s Alloc=%d/%d Heap=%d NextGC=%d Mallocs=%d\n", name, cpus, st.Alloc, st.TotalAlloc, st.Sys, st.NextGC, st.Mallocs)
+	fmt.Printf("garbage.%s%s %d %d ns/op\n", name, cpus, n, t.Nanoseconds()/int64(n))
+	fmt.Printf("garbage.%sLastPause%s 1 %d ns/op\n", name, cpus, st.PauseNs[(st.NumGC-1)%uint32(len(st.PauseNs))])
+	fmt.Printf("garbage.%sPause%s %d %d ns/op\n", name, cpus, st.NumGC, int64(st.PauseTotalNs)/int64(st.NumGC))
 	nn := int(st.NumGC)
 	if nn >= len(st.PauseNs) {
 		nn = len(st.PauseNs)
 	}
 	t1, t2, t3, t4, t5 := tukey5(st.PauseNs[0:nn])
-	fmt.Printf("garbage.%sPause5: %d %d %d %d %d\n", name, t1, t2, t3, t4, t5)
+	fmt.Printf("garbage.%sPause5%s: %d %d %d %d %d\n", name, cpus, t1, t2, t3, t4, t5)
 
 	//	fmt.Printf("garbage.%sScan: %v\n", name, st.ScanDist)
 }

test/bench/garbage/tree2.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"runtime"
 	"runtime/pprof"
+	"time"
 	"unsafe"
 )
 
@@ -83,7 +84,12 @@ func main() {
 		pprof.StartCPUProfile(f)
 		defer pprof.StopCPUProfile()
 	}
-	for i := 0; i < 10; i++ {
+	const N = 10
+	var t0 time.Time
+	for i := 0; i < N; i++ {
+		t0 = time.Now()
 		gc()
 	}
+	// Standard gotest benchmark output, collected by build dashboard.
+	gcstats("BenchmarkTree2", N, time.Now().Sub(t0))
 }