encoding/json: add marshal/unmarshal benchmark

R=bradfitz
CC=golang-dev
https://golang.org/cl/5387041

diff --git a/src/pkg/encoding/json/bench_test.go b/src/pkg/encoding/json/bench_test.go
new file mode 100644 (file)
index 0000000..f0c5201
--- /dev/null
+++ b/src/pkg/encoding/json/bench_test.go
@@ -0,0 +1,157 @@
+// 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"
+       "io/ioutil"
+       "os"
+       "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) {
+       if codeJSON == nil {
+               b.StopTimer()
+               codeInit()
+               b.StartTimer()
+       }
+       enc := NewEncoder(ioutil.Discard)
+       for i := 0; i < b.N; i++ {
+               if err := enc.Encode(&codeStruct); err != nil {
+                       panic(err)
+               }
+       }
+       b.SetBytes(int64(len(codeJSON)))
+}
+
+func BenchmarkCodeMarshal(b *testing.B) {
+       if codeJSON == nil {
+               b.StopTimer()
+               codeInit()
+               b.StartTimer()
+       }
+       for i := 0; i < b.N; i++ {
+               if _, err := Marshal(&codeStruct); err != nil {
+                       panic(err)
+               }
+       }
+       b.SetBytes(int64(len(codeJSON)))
+}
+
+func BenchmarkCodeDecoder(b *testing.B) {
+       if codeJSON == nil {
+               b.StopTimer()
+               codeInit()
+               b.StartTimer()
+       }
+       var buf bytes.Buffer
+       dec := NewDecoder(&buf)
+       var r codeResponse
+       for i := 0; i < b.N; i++ {
+               buf.Write(codeJSON)
+               // hide EOF
+               buf.WriteByte('\n')
+               buf.WriteByte('\n')
+               buf.WriteByte('\n')
+               if err := dec.Decode(&r); err != nil {
+                       panic(err)
+               }
+       }
+       b.SetBytes(int64(len(codeJSON)))
+}
+
+func BenchmarkCodeUnmarshal(b *testing.B) {
+       if codeJSON == nil {
+               b.StopTimer()
+               codeInit()
+               b.StartTimer()
+       }
+       for i := 0; i < b.N; i++ {
+               var r codeResponse
+               if err := Unmarshal(codeJSON, &r); err != nil {
+                       panic(err)
+               }
+       }
+       b.SetBytes(int64(len(codeJSON)))
+}
+
+func BenchmarkCodeUnmarshalReuse(b *testing.B) {
+       if codeJSON == nil {
+               b.StopTimer()
+               codeInit()
+               b.StartTimer()
+       }
+       var r codeResponse
+       for i := 0; i < b.N; i++ {
+               if err := Unmarshal(codeJSON, &r); err != nil {
+                       panic(err)
+               }
+       }
+       b.SetBytes(int64(len(codeJSON)))
+}

diff --git a/src/pkg/encoding/json/testdata/code.json.gz b/src/pkg/encoding/json/testdata/code.json.gz
new file mode 100644 (file)
index 0000000..0e2895b
Binary files /dev/null and b/src/pkg/encoding/json/testdata/code.json.gz differ