diff options
Diffstat (limited to 'src/testing/benchmark.go')
| -rw-r--r-- | src/testing/benchmark.go | 141 |
1 files changed, 78 insertions, 63 deletions
diff --git a/src/testing/benchmark.go b/src/testing/benchmark.go index f6c832f51..4647cfe93 100644 --- a/src/testing/benchmark.go +++ b/src/testing/benchmark.go @@ -18,8 +18,26 @@ type benchTimeFlag struct { d time.Duration } -// B is a type passed to Benchmark functions to manage benchmark timing and to -// specify the number of iterations to run. +// InternalBenchmark is an internal type but exported because it is cross-package; +// it is part of the implementation of the "go test" command. +type InternalBenchmark struct { + Name string + F func(b *B) +} + +// B is a type passed to Benchmark functions to manage benchmark +// timing and to specify the number of iterations to run. +// +// A benchmark ends when its Benchmark function returns or calls any of the methods +// FailNow, Fatal, Fatalf, SkipNow, Skip, or Skipf. Those methods must be called +// only from the goroutine running the Benchmark function. +// The other reporting methods, such as the variations of Log and Error, +// may be called simultaneously from multiple goroutines. +// +// Like in tests, benchmark logs are accumulated during execution +// and dumped to standard output when done. Unlike in tests, benchmark logs +// are always printed, so as not to hide output whose existence may be +// affecting benchmark results. type B struct { common hasSub bool // TODO: should be in common, and atomic @@ -32,49 +50,6 @@ type B struct { result BenchmarkResult } -// InternalBenchmark is an internal type but exported because it is cross-package; -// it is part of the implementation of the "go test" command. -type InternalBenchmark struct { - Name string - F func(b *B) -} - -// BenchmarkResult contains the results of a benchmark run. -type BenchmarkResult struct { - N int // The number of iterations. - T time.Duration // The total time taken. -} - -// NsPerOp returns the "ns/op" metric. -func (r BenchmarkResult) NsPerOp() int64 { - if r.N <= 0 { - return 0 - } - return r.T.Nanoseconds() / int64(r.N) -} - -// AllocsPerOp returns the "allocs/op" metric, -// which is calculated as r.MemAllocs / r.N. -func (r BenchmarkResult) AllocsPerOp() int64 { - return 0 // Dummy version to allow running e.g. golang.org/test/fibo.go -} - -// AllocedBytesPerOp returns the "B/op" metric, -// which is calculated as r.MemBytes / r.N. -func (r BenchmarkResult) AllocedBytesPerOp() int64 { - return 0 // Dummy version to allow running e.g. golang.org/test/fibo.go -} - -func (b *B) SetBytes(n int64) { - panic("testing: unimplemented: B.SetBytes") -} - -// ReportAllocs enables malloc statistics for this benchmark. -func (b *B) ReportAllocs() { - // Dummy version to allow building e.g. golang.org/crypto/... - panic("testing: unimplemented: B.ReportAllocs") -} - // StartTimer starts timing a test. This function is called automatically // before a benchmark starts, but it can also be used to resume timing after // a call to StopTimer. @@ -95,8 +70,8 @@ func (b *B) StopTimer() { } } -// ResetTimer zeroes the elapsed benchmark time. -// It does not affect whether the timer is running. +// ResetTimer zeroes the elapsed benchmark time and memory allocation counters +// and deletes user-reported metrics. func (b *B) ResetTimer() { if b.timerOn { b.start = time.Now() @@ -104,6 +79,19 @@ func (b *B) ResetTimer() { b.duration = 0 } +// SetBytes records the number of bytes processed in a single operation. +// If this is called, the benchmark will report ns/op and MB/s. +func (b *B) SetBytes(n int64) { + panic("testing: unimplemented: B.SetBytes") +} + +// ReportAllocs enables malloc statistics for this benchmark. +// It is equivalent to setting -test.benchmem, but it only affects the +// benchmark function that calls ReportAllocs. +func (b *B) ReportAllocs() { + panic("testing: unimplemented: B.ReportAllocs") +} + // runN runs a single benchmark for the specified number of iterations. func (b *B) runN(n int) { b.N = n @@ -173,6 +161,32 @@ func (b *B) launch() { b.result = BenchmarkResult{b.N, b.duration} } +// BenchmarkResult contains the results of a benchmark run. +type BenchmarkResult struct { + N int // The number of iterations. + T time.Duration // The total time taken. +} + +// NsPerOp returns the "ns/op" metric. +func (r BenchmarkResult) NsPerOp() int64 { + if r.N <= 0 { + return 0 + } + return r.T.Nanoseconds() / int64(r.N) +} + +// AllocsPerOp returns the "allocs/op" metric, +// which is calculated as r.MemAllocs / r.N. +func (r BenchmarkResult) AllocsPerOp() int64 { + return 0 // Dummy version to allow running e.g. golang.org/test/fibo.go +} + +// AllocedBytesPerOp returns the "B/op" metric, +// which is calculated as r.MemBytes / r.N. +func (r BenchmarkResult) AllocedBytesPerOp() int64 { + return 0 // Dummy version to allow running e.g. golang.org/test/fibo.go +} + // Run benchmarks f as a subbenchmark with the given name. It reports // true if the subbenchmark succeeded. // @@ -192,22 +206,6 @@ func (b *B) Run(name string, f func(b *B)) bool { return !sub.failed } -// Benchmark benchmarks a single function. It is useful for creating -// custom benchmarks that do not use the "go test" command. -// -// If f calls Run, the result will be an estimate of running all its -// subbenchmarks that don't call Run in sequence in a single benchmark. -func Benchmark(f func(b *B)) BenchmarkResult { - b := &B{ - benchFunc: f, - benchTime: benchTime, - } - if b.run1() { - b.run() - } - return b.result -} - // add simulates running benchmarks in sequence in a single iteration. It is // used to give some meaningful results in case func Benchmark is used in // combination with Run. @@ -234,3 +232,20 @@ func (pb *PB) Next() bool { func (b *B) RunParallel(body func(*PB)) { return } + +// Benchmark benchmarks a single function. It is useful for creating +// custom benchmarks that do not use the "go test" command. +// +// If f calls Run, the result will be an estimate of running all its +// subbenchmarks that don't call Run in sequence in a single benchmark. +func Benchmark(f func(b *B)) BenchmarkResult { + b := &B{ + benchFunc: f, + benchTime: benchTime, + } + if b.run1() { + b.run() + } + return b.result +} + |