src/encoding/json/bench_test.go - go - Git at Google

 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 // Large data benchmark.
 // The JSON data is a summary of agl's changes in the
 // go, webkit, and chromium open source projects.
 // We benchmark converting between the JSON form
 // and in-memory data structures.

 package json

 import (
 	"bytes"
 	"compress/gzip"
 	"fmt"
 	"internal/testenv"
 	"io/ioutil"
 	"os"
 	"reflect"
 	"runtime"
 	"strings"
 	"sync"
 	"testing"
 )

 type codeResponse struct {
 	Tree     *codeNode `json:"tree"`
 	Username string    `json:"username"`
 }

 type codeNode struct {
 	Name     string      `json:"name"`
 	Kids     []*codeNode `json:"kids"`
 	CLWeight float64     `json:"cl_weight"`
 	Touches  int         `json:"touches"`
 	MinT     int64       `json:"min_t"`
 	MaxT     int64       `json:"max_t"`
 	MeanT    int64       `json:"mean_t"`
 }

 var codeJSON []byte
 var codeStruct codeResponse

 func codeInit() {
 	f, err := os.Open("testdata/code.json.gz")
 	if err != nil {
 		panic(err)
 	}
 	defer f.Close()
 	gz, err := gzip.NewReader(f)
 	if err != nil {
 		panic(err)
 	}
 	data, err := ioutil.ReadAll(gz)
 	if err != nil {
 		panic(err)
 	}

 	codeJSON = data

 	if err := Unmarshal(codeJSON, &codeStruct); err != nil {
 		panic("unmarshal code.json: " + err.Error())
 	}

 	if data, err = Marshal(&codeStruct); err != nil {
 		panic("marshal code.json: " + err.Error())
 	}

 	if !bytes.Equal(data, codeJSON) {
 		println("different lengths", len(data), len(codeJSON))
 		for i := 0; i < len(data) && i < len(codeJSON); i++ {
 			if data[i] != codeJSON[i] {
 				println("re-marshal: changed at byte", i)
 				println("orig: ", string(codeJSON[i-10:i+10]))
 				println("new: ", string(data[i-10:i+10]))
 				break
 			}
 		}
 		panic("re-marshal code.json: different result")
 	}
 }

 func BenchmarkCodeEncoder(b *testing.B) {
 	b.ReportAllocs()
 	if codeJSON == nil {
 		b.StopTimer()
 		codeInit()
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
 		enc := NewEncoder(ioutil.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&codeStruct); err != nil {
 				b.Fatal("Encode:", err)
 			}
 		}
 	})
 	b.SetBytes(int64(len(codeJSON)))
 }

 func BenchmarkCodeMarshal(b *testing.B) {
 	b.ReportAllocs()
 	if codeJSON == nil {
 		b.StopTimer()
 		codeInit()
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
 			if _, err := Marshal(&codeStruct); err != nil {
 				b.Fatal("Marshal:", err)
 			}
 		}
 	})
 	b.SetBytes(int64(len(codeJSON)))
 }

 func benchMarshalBytes(n int) func(*testing.B) {
 	sample := []byte("hello world")
 	// Use a struct pointer, to avoid an allocation when passing it as an
 	// interface parameter to Marshal.
 	v := &struct {
 		Bytes []byte
 	}{
 		bytes.Repeat(sample, (n/len(sample))+1)[:n],
 	}
 	return func(b *testing.B) {
 		for i := 0; i < b.N; i++ {
 			if _, err := Marshal(v); err != nil {
 				b.Fatal("Marshal:", err)
 			}
 		}
 	}
 }

 func BenchmarkMarshalBytes(b *testing.B) {
 	b.ReportAllocs()
 	// 32 fits within encodeState.scratch.
 	b.Run("32", benchMarshalBytes(32))
 	// 256 doesn't fit in encodeState.scratch, but is small enough to
 	// allocate and avoid the slower base64.NewEncoder.
 	b.Run("256", benchMarshalBytes(256))
 	// 4096 is large enough that we want to avoid allocating for it.
 	b.Run("4096", benchMarshalBytes(4096))
 }

 func BenchmarkCodeDecoder(b *testing.B) {
 	b.ReportAllocs()
 	if codeJSON == nil {
 		b.StopTimer()
 		codeInit()
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
 		var buf bytes.Buffer
 		dec := NewDecoder(&buf)
 		var r codeResponse
 		for pb.Next() {
 			buf.Write(codeJSON)
 			// hide EOF
 			buf.WriteByte('\n')
 			buf.WriteByte('\n')
 			buf.WriteByte('\n')
 			if err := dec.Decode(&r); err != nil {
 				b.Fatal("Decode:", err)
 			}
 		}
 	})
 	b.SetBytes(int64(len(codeJSON)))
 }

 func BenchmarkUnicodeDecoder(b *testing.B) {
 	b.ReportAllocs()
 	j := []byte(`"\uD83D\uDE01"`)
 	b.SetBytes(int64(len(j)))
 	r := bytes.NewReader(j)
 	dec := NewDecoder(r)
 	var out string
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
 		if err := dec.Decode(&out); err != nil {
 			b.Fatal("Decode:", err)
 		}
 		r.Seek(0, 0)
 	}
 }

 func BenchmarkDecoderStream(b *testing.B) {
 	b.ReportAllocs()
 	b.StopTimer()
 	var buf bytes.Buffer
 	dec := NewDecoder(&buf)
 	buf.WriteString(`"` + strings.Repeat("x", 1000000) + `"` + "\n\n\n")
 	var x interface{}
 	if err := dec.Decode(&x); err != nil {
 		b.Fatal("Decode:", err)
 	}
 	ones := strings.Repeat(" 1\n", 300000) + "\n\n\n"
 	b.StartTimer()
 	for i := 0; i < b.N; i++ {
 		if i%300000 == 0 {
 			buf.WriteString(ones)
 		}
 		x = nil
 		if err := dec.Decode(&x); err != nil || x != 1.0 {
 			b.Fatalf("Decode: %v after %d", err, i)
 		}
 	}
 }

 func BenchmarkCodeUnmarshal(b *testing.B) {
 	b.ReportAllocs()
 	if codeJSON == nil {
 		b.StopTimer()
 		codeInit()
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
 			var r codeResponse
 			if err := Unmarshal(codeJSON, &r); err != nil {
 				b.Fatal("Unmarshal:", err)
 			}
 		}
 	})
 	b.SetBytes(int64(len(codeJSON)))
 }

 func BenchmarkCodeUnmarshalReuse(b *testing.B) {
 	b.ReportAllocs()
 	if codeJSON == nil {
 		b.StopTimer()
 		codeInit()
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
 		var r codeResponse
 		for pb.Next() {
 			if err := Unmarshal(codeJSON, &r); err != nil {
 				b.Fatal("Unmarshal:", err)
 			}
 		}
 	})
 	b.SetBytes(int64(len(codeJSON)))
 }

 func BenchmarkUnmarshalString(b *testing.B) {
 	b.ReportAllocs()
 	data := []byte(`"hello, world"`)
 	b.RunParallel(func(pb *testing.PB) {
 		var s string
 		for pb.Next() {
 			if err := Unmarshal(data, &s); err != nil {
 				b.Fatal("Unmarshal:", err)
 			}
 		}
 	})
 }

 func BenchmarkUnmarshalFloat64(b *testing.B) {
 	b.ReportAllocs()
 	data := []byte(`3.14`)
 	b.RunParallel(func(pb *testing.PB) {
 		var f float64
 		for pb.Next() {
 			if err := Unmarshal(data, &f); err != nil {
 				b.Fatal("Unmarshal:", err)
 			}
 		}
 	})
 }

 func BenchmarkUnmarshalInt64(b *testing.B) {
 	b.ReportAllocs()
 	data := []byte(`3`)
 	b.RunParallel(func(pb *testing.PB) {
 		var x int64
 		for pb.Next() {
 			if err := Unmarshal(data, &x); err != nil {
 				b.Fatal("Unmarshal:", err)
 			}
 		}
 	})
 }

 func BenchmarkIssue10335(b *testing.B) {
 	b.ReportAllocs()
 	j := []byte(`{"a":{ }}`)
 	b.RunParallel(func(pb *testing.PB) {
 		var s struct{}
 		for pb.Next() {
 			if err := Unmarshal(j, &s); err != nil {
 				b.Fatal(err)
 			}
 		}
 	})
 }

 func BenchmarkIssue34127(b *testing.B) {
 	b.ReportAllocs()
 	j := struct {
 		Bar string `json:"bar,string"`
 	}{
 		Bar: `foobar`,
 	}
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
 			if _, err := Marshal(&j); err != nil {
 				b.Fatal(err)
 			}
 		}
 	})
 }

 func BenchmarkUnmapped(b *testing.B) {
 	b.ReportAllocs()
 	j := []byte(`{"s": "hello", "y": 2, "o": {"x": 0}, "a": [1, 99, {"x": 1}]}`)
 	b.RunParallel(func(pb *testing.PB) {
 		var s struct{}
 		for pb.Next() {
 			if err := Unmarshal(j, &s); err != nil {
 				b.Fatal(err)
 			}
 		}
 	})
 }

 func BenchmarkTypeFieldsCache(b *testing.B) {
 	b.ReportAllocs()
 	var maxTypes int = 1e6
 	if testenv.Builder() != "" {
 		maxTypes = 1e3 // restrict cache sizes on builders
 	}

 	// Dynamically generate many new types.
 	types := make([]reflect.Type, maxTypes)
 	fs := []reflect.StructField{{
 		Type:  reflect.TypeOf(""),
 		Index: []int{0},
 	}}
 	for i := range types {
 		fs[0].Name = fmt.Sprintf("TypeFieldsCache%d", i)
 		types[i] = reflect.StructOf(fs)
 	}

 	// clearClear clears the cache. Other JSON operations, must not be running.
 	clearCache := func() {
 		fieldCache = sync.Map{}
 	}

 	// MissTypes tests the performance of repeated cache misses.
 	// This measures the time to rebuild a cache of size nt.
 	for nt := 1; nt <= maxTypes; nt *= 10 {
 		ts := types[:nt]
 		b.Run(fmt.Sprintf("MissTypes%d", nt), func(b *testing.B) {
 			nc := runtime.GOMAXPROCS(0)
 			for i := 0; i < b.N; i++ {
 				clearCache()
 				var wg sync.WaitGroup
 				for j := 0; j < nc; j++ {
 					wg.Add(1)
 					go func(j int) {
 						for _, t := range ts[(j*len(ts))/nc : ((j+1)*len(ts))/nc] {
 							cachedTypeFields(t)
 						}
 						wg.Done()
 					}(j)
 				}
 				wg.Wait()
 			}
 		})
 	}

 	// HitTypes tests the performance of repeated cache hits.
 	// This measures the average time of each cache lookup.
 	for nt := 1; nt <= maxTypes; nt *= 10 {
 		// Pre-warm a cache of size nt.
 		clearCache()
 		for _, t := range types[:nt] {
 			cachedTypeFields(t)
 		}
 		b.Run(fmt.Sprintf("HitTypes%d", nt), func(b *testing.B) {
 			b.RunParallel(func(pb *testing.PB) {
 				for pb.Next() {
 					cachedTypeFields(types[0])
 				}
 			})
 		})
 	}
 }

 func BenchmarkEncodeMarshaler(b *testing.B) {
 	b.ReportAllocs()

 	m := struct {
 		A int
 		B RawMessage
 	}{}

 	b.RunParallel(func(pb *testing.PB) {
 		enc := NewEncoder(ioutil.Discard)

 		for pb.Next() {
 			if err := enc.Encode(&m); err != nil {
 				b.Fatal("Encode:", err)
 			}
 		}
 	})
 }
	// Copyright 2011 The Go Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	// Large data benchmark.
	// The JSON data is a summary of agl's changes in the
	// go, webkit, and chromium open source projects.
	// We benchmark converting between the JSON form
	// and in-memory data structures.

	package json

	import (
	"bytes"
	"compress/gzip"
	"fmt"
	"internal/testenv"
	"io/ioutil"
	"os"
	"reflect"
	"runtime"
	"strings"
	"sync"
	"testing"
	)

	type codeResponse struct {
	Tree *codeNode `json:"tree"`
	Username string `json:"username"`
	}

	type codeNode struct {
	Name string `json:"name"`
	Kids []*codeNode `json:"kids"`
	CLWeight float64 `json:"cl_weight"`
	Touches int `json:"touches"`
	MinT int64 `json:"min_t"`
	MaxT int64 `json:"max_t"`
	MeanT int64 `json:"mean_t"`
	}

	var codeJSON []byte
	var codeStruct codeResponse

	func codeInit() {
	f, err := os.Open("testdata/code.json.gz")
	if err != nil {
	panic(err)
	}
	defer f.Close()
	gz, err := gzip.NewReader(f)
	if err != nil {
	panic(err)
	}
	data, err := ioutil.ReadAll(gz)
	if err != nil {
	panic(err)
	}

	codeJSON = data

	if err := Unmarshal(codeJSON, &codeStruct); err != nil {
	panic("unmarshal code.json: " + err.Error())
	}

	if data, err = Marshal(&codeStruct); err != nil {
	panic("marshal code.json: " + err.Error())
	}

	if !bytes.Equal(data, codeJSON) {
	println("different lengths", len(data), len(codeJSON))
	for i := 0; i < len(data) && i < len(codeJSON); i++ {
	if data[i] != codeJSON[i] {
	println("re-marshal: changed at byte", i)
	println("orig: ", string(codeJSON[i-10:i+10]))
	println("new: ", string(data[i-10:i+10]))
	break
	}
	}
	panic("re-marshal code.json: different result")
	}
	}

	func BenchmarkCodeEncoder(b *testing.B) {
	b.ReportAllocs()
	if codeJSON == nil {
	b.StopTimer()
	codeInit()
	b.StartTimer()
	}
	b.RunParallel(func(pb *testing.PB) {
	enc := NewEncoder(ioutil.Discard)
	for pb.Next() {
	if err := enc.Encode(&codeStruct); err != nil {
	b.Fatal("Encode:", err)
	}
	}
	})
	b.SetBytes(int64(len(codeJSON)))
	}

	func BenchmarkCodeMarshal(b *testing.B) {
	b.ReportAllocs()
	if codeJSON == nil {
	b.StopTimer()
	codeInit()
	b.StartTimer()
	}
	b.RunParallel(func(pb *testing.PB) {
	for pb.Next() {
	if _, err := Marshal(&codeStruct); err != nil {
	b.Fatal("Marshal:", err)
	}
	}
	})
	b.SetBytes(int64(len(codeJSON)))
	}

	func benchMarshalBytes(n int) func(*testing.B) {
	sample := []byte("hello world")
	// Use a struct pointer, to avoid an allocation when passing it as an
	// interface parameter to Marshal.
	v := &struct {
	Bytes []byte
	}{
	bytes.Repeat(sample, (n/len(sample))+1)[:n],
	}
	return func(b *testing.B) {
	for i := 0; i < b.N; i++ {
	if _, err := Marshal(v); err != nil {
	b.Fatal("Marshal:", err)
	}
	}
	}
	}

	func BenchmarkMarshalBytes(b *testing.B) {
	b.ReportAllocs()
	// 32 fits within encodeState.scratch.
	b.Run("32", benchMarshalBytes(32))
	// 256 doesn't fit in encodeState.scratch, but is small enough to
	// allocate and avoid the slower base64.NewEncoder.
	b.Run("256", benchMarshalBytes(256))
	// 4096 is large enough that we want to avoid allocating for it.
	b.Run("4096", benchMarshalBytes(4096))
	}

	func BenchmarkCodeDecoder(b *testing.B) {
	b.ReportAllocs()
	if codeJSON == nil {
	b.StopTimer()
	codeInit()
	b.StartTimer()
	}
	b.RunParallel(func(pb *testing.PB) {
	var buf bytes.Buffer
	dec := NewDecoder(&buf)
	var r codeResponse
	for pb.Next() {
	buf.Write(codeJSON)
	// hide EOF
	buf.WriteByte('\n')
	buf.WriteByte('\n')
	buf.WriteByte('\n')
	if err := dec.Decode(&r); err != nil {
	b.Fatal("Decode:", err)
	}
	}
	})
	b.SetBytes(int64(len(codeJSON)))
	}

	func BenchmarkUnicodeDecoder(b *testing.B) {
	b.ReportAllocs()
	j := []byte(`"\uD83D\uDE01"`)
	b.SetBytes(int64(len(j)))
	r := bytes.NewReader(j)
	dec := NewDecoder(r)
	var out string
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
	if err := dec.Decode(&out); err != nil {
	b.Fatal("Decode:", err)
	}
	r.Seek(0, 0)
	}
	}

	func BenchmarkDecoderStream(b *testing.B) {
	b.ReportAllocs()
	b.StopTimer()
	var buf bytes.Buffer
	dec := NewDecoder(&buf)
	buf.WriteString(`"` + strings.Repeat("x", 1000000) + `"` + "\n\n\n")
	var x interface{}
	if err := dec.Decode(&x); err != nil {
	b.Fatal("Decode:", err)
	}
	ones := strings.Repeat(" 1\n", 300000) + "\n\n\n"
	b.StartTimer()
	for i := 0; i < b.N; i++ {
	if i%300000 == 0 {
	buf.WriteString(ones)
	}
	x = nil
	if err := dec.Decode(&x); err != nil \|\| x != 1.0 {
	b.Fatalf("Decode: %v after %d", err, i)
	}
	}
	}

	func BenchmarkCodeUnmarshal(b *testing.B) {
	b.ReportAllocs()
	if codeJSON == nil {
	b.StopTimer()
	codeInit()
	b.StartTimer()
	}
	b.RunParallel(func(pb *testing.PB) {
	for pb.Next() {
	var r codeResponse
	if err := Unmarshal(codeJSON, &r); err != nil {
	b.Fatal("Unmarshal:", err)
	}
	}
	})
	b.SetBytes(int64(len(codeJSON)))
	}

	func BenchmarkCodeUnmarshalReuse(b *testing.B) {
	b.ReportAllocs()
	if codeJSON == nil {
	b.StopTimer()
	codeInit()
	b.StartTimer()
	}
	b.RunParallel(func(pb *testing.PB) {
	var r codeResponse
	for pb.Next() {
	if err := Unmarshal(codeJSON, &r); err != nil {
	b.Fatal("Unmarshal:", err)
	}
	}
	})
	b.SetBytes(int64(len(codeJSON)))
	}

	func BenchmarkUnmarshalString(b *testing.B) {
	b.ReportAllocs()
	data := []byte(`"hello, world"`)
	b.RunParallel(func(pb *testing.PB) {
	var s string
	for pb.Next() {
	if err := Unmarshal(data, &s); err != nil {
	b.Fatal("Unmarshal:", err)
	}
	}
	})
	}

	func BenchmarkUnmarshalFloat64(b *testing.B) {
	b.ReportAllocs()
	data := []byte(`3.14`)
	b.RunParallel(func(pb *testing.PB) {
	var f float64
	for pb.Next() {
	if err := Unmarshal(data, &f); err != nil {
	b.Fatal("Unmarshal:", err)
	}
	}
	})
	}

	func BenchmarkUnmarshalInt64(b *testing.B) {
	b.ReportAllocs()
	data := []byte(`3`)
	b.RunParallel(func(pb *testing.PB) {
	var x int64
	for pb.Next() {
	if err := Unmarshal(data, &x); err != nil {
	b.Fatal("Unmarshal:", err)
	}
	}
	})
	}

	func BenchmarkIssue10335(b *testing.B) {
	b.ReportAllocs()
	j := []byte(`{"a":{ }}`)
	b.RunParallel(func(pb *testing.PB) {
	var s struct{}
	for pb.Next() {
	if err := Unmarshal(j, &s); err != nil {
	b.Fatal(err)
	}
	}
	})
	}

	func BenchmarkIssue34127(b *testing.B) {
	b.ReportAllocs()
	j := struct {
	Bar string `json:"bar,string"`
	}{
	Bar: `foobar`,
	}
	b.RunParallel(func(pb *testing.PB) {
	for pb.Next() {
	if _, err := Marshal(&j); err != nil {
	b.Fatal(err)
	}
	}
	})
	}

	func BenchmarkUnmapped(b *testing.B) {
	b.ReportAllocs()
	j := []byte(`{"s": "hello", "y": 2, "o": {"x": 0}, "a": [1, 99, {"x": 1}]}`)
	b.RunParallel(func(pb *testing.PB) {
	var s struct{}
	for pb.Next() {
	if err := Unmarshal(j, &s); err != nil {
	b.Fatal(err)
	}
	}
	})
	}

	func BenchmarkTypeFieldsCache(b *testing.B) {
	b.ReportAllocs()
	var maxTypes int = 1e6
	if testenv.Builder() != "" {
	maxTypes = 1e3 // restrict cache sizes on builders
	}

	// Dynamically generate many new types.
	types := make([]reflect.Type, maxTypes)
	fs := []reflect.StructField{{
	Type: reflect.TypeOf(""),
	Index: []int{0},
	}}
	for i := range types {
	fs[0].Name = fmt.Sprintf("TypeFieldsCache%d", i)
	types[i] = reflect.StructOf(fs)
	}

	// clearClear clears the cache. Other JSON operations, must not be running.
	clearCache := func() {
	fieldCache = sync.Map{}
	}

	// MissTypes tests the performance of repeated cache misses.
	// This measures the time to rebuild a cache of size nt.
	for nt := 1; nt <= maxTypes; nt *= 10 {
	ts := types[:nt]
	b.Run(fmt.Sprintf("MissTypes%d", nt), func(b *testing.B) {
	nc := runtime.GOMAXPROCS(0)
	for i := 0; i < b.N; i++ {
	clearCache()
	var wg sync.WaitGroup
	for j := 0; j < nc; j++ {
	wg.Add(1)
	go func(j int) {
	for _, t := range ts[(jlen(ts))/nc : ((j+1)len(ts))/nc] {
	cachedTypeFields(t)
	}
	wg.Done()
	}(j)
	}
	wg.Wait()
	}
	})
	}

	// HitTypes tests the performance of repeated cache hits.
	// This measures the average time of each cache lookup.
	for nt := 1; nt <= maxTypes; nt *= 10 {
	// Pre-warm a cache of size nt.
	clearCache()
	for _, t := range types[:nt] {
	cachedTypeFields(t)
	}
	b.Run(fmt.Sprintf("HitTypes%d", nt), func(b *testing.B) {
	b.RunParallel(func(pb *testing.PB) {
	for pb.Next() {
	cachedTypeFields(types[0])
	}
	})
	})
	}
	}

	func BenchmarkEncodeMarshaler(b *testing.B) {
	b.ReportAllocs()

	m := struct {
	A int
	B RawMessage
	}{}

	b.RunParallel(func(pb *testing.PB) {
	enc := NewEncoder(ioutil.Discard)

	for pb.Next() {
	if err := enc.Encode(&m); err != nil {
	b.Fatal("Encode:", err)
	}
	}
	})
	}