diff options
Diffstat (limited to 'libgo/go/testing/benchmark.go')
| -rw-r--r-- | libgo/go/testing/benchmark.go | 66 |
1 files changed, 59 insertions, 7 deletions
diff --git a/libgo/go/testing/benchmark.go b/libgo/go/testing/benchmark.go index 4129059..cb92fab 100644 --- a/libgo/go/testing/benchmark.go +++ b/libgo/go/testing/benchmark.go @@ -9,11 +9,19 @@ import ( "fmt" "os" "runtime" + "sync" "time" ) var matchBenchmarks = flag.String("test.bench", "", "regular expression to select benchmarks to run") -var benchTime = flag.Float64("test.benchtime", 1, "approximate run time for each benchmark, in seconds") +var benchTime = flag.Duration("test.benchtime", 1*time.Second, "approximate run time for each benchmark") +var benchmarkMemory = flag.Bool("test.benchmem", false, "print memory allocations for benchmarks") + +// Global lock to ensure only one benchmark runs at a time. +var benchmarkLock sync.Mutex + +// Used for every benchmark for measuring memory. +var memStats runtime.MemStats // An internal type but exported because it is cross-package; part of the implementation // of the "go test" command. @@ -31,6 +39,12 @@ type B struct { bytes int64 timerOn bool result BenchmarkResult + // The initial states of memStats.Mallocs and memStats.TotalAlloc. + startAllocs uint64 + startBytes uint64 + // The net total of this test after being run. + netAllocs uint64 + netBytes uint64 } // StartTimer starts timing a test. This function is called automatically @@ -38,6 +52,9 @@ type B struct { // a call to StopTimer. func (b *B) StartTimer() { if !b.timerOn { + runtime.ReadMemStats(&memStats) + b.startAllocs = memStats.Mallocs + b.startBytes = memStats.TotalAlloc b.start = time.Now() b.timerOn = true } @@ -49,6 +66,9 @@ func (b *B) StartTimer() { func (b *B) StopTimer() { if b.timerOn { b.duration += time.Now().Sub(b.start) + runtime.ReadMemStats(&memStats) + b.netAllocs += memStats.Mallocs - b.startAllocs + b.netBytes += memStats.TotalAlloc - b.startBytes b.timerOn = false } } @@ -57,9 +77,14 @@ func (b *B) StopTimer() { // It does not affect whether the timer is running. func (b *B) ResetTimer() { if b.timerOn { + runtime.ReadMemStats(&memStats) + b.startAllocs = memStats.Mallocs + b.startBytes = memStats.TotalAlloc b.start = time.Now() } b.duration = 0 + b.netAllocs = 0 + b.netBytes = 0 } // SetBytes records the number of bytes processed in a single operation. @@ -75,6 +100,8 @@ func (b *B) nsPerOp() int64 { // runN runs a single benchmark for the specified number of iterations. func (b *B) runN(n int) { + benchmarkLock.Lock() + defer benchmarkLock.Unlock() // Try to get a comparable environment for each run // by clearing garbage from previous runs. runtime.GC() @@ -151,7 +178,7 @@ func (b *B) launch() { b.runN(n) // Run the benchmark for at least the specified amount of time. - d := time.Duration(*benchTime * float64(time.Second)) + d := *benchTime for !b.failed && b.duration < d && n < 1e9 { last := n // Predict iterations/sec. @@ -168,14 +195,16 @@ func (b *B) launch() { n = roundUp(n) b.runN(n) } - b.result = BenchmarkResult{b.N, b.duration, b.bytes} + b.result = BenchmarkResult{b.N, b.duration, b.bytes, b.netAllocs, b.netBytes} } // The results of a benchmark run. type BenchmarkResult struct { - N int // The number of iterations. - T time.Duration // The total time taken. - Bytes int64 // Bytes processed in one iteration. + N int // The number of iterations. + T time.Duration // The total time taken. + Bytes int64 // Bytes processed in one iteration. + MemAllocs uint64 // The total number of memory allocations. + MemBytes uint64 // The total number of bytes allocated. } func (r BenchmarkResult) NsPerOp() int64 { @@ -192,6 +221,20 @@ func (r BenchmarkResult) mbPerSec() float64 { return (float64(r.Bytes) * float64(r.N) / 1e6) / r.T.Seconds() } +func (r BenchmarkResult) AllocsPerOp() int64 { + if r.N <= 0 { + return 0 + } + return int64(r.MemAllocs) / int64(r.N) +} + +func (r BenchmarkResult) AllocedBytesPerOp() int64 { + if r.N <= 0 { + return 0 + } + return int64(r.MemBytes) / int64(r.N) +} + func (r BenchmarkResult) String() string { mbs := r.mbPerSec() mb := "" @@ -212,6 +255,11 @@ func (r BenchmarkResult) String() string { return fmt.Sprintf("%8d\t%s%s", r.N, ns, mb) } +func (r BenchmarkResult) MemString() string { + return fmt.Sprintf("%8d B/op\t%8d allocs/op", + r.AllocedBytesPerOp(), r.AllocsPerOp()) +} + // An internal function but exported because it is cross-package; part of the implementation // of the "go test" command. func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) { @@ -249,7 +297,11 @@ func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks [ fmt.Printf("--- FAIL: %s\n%s", benchName, b.output) continue } - fmt.Printf("%v\n", r) + results := r.String() + if *benchmarkMemory { + results += "\t" + r.MemString() + } + fmt.Println(results) // Unlike with tests, we ignore the -chatty flag and always print output for // benchmarks since the output generation time will skew the results. if len(b.output) > 0 { |