diff options
Diffstat (limited to 'src/encoding/json/encode.go')
| -rw-r--r-- | src/encoding/json/encode.go | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/src/encoding/json/encode.go b/src/encoding/json/encode.go index 632c12404a..d5fe4d6b78 100644 --- a/src/encoding/json/encode.go +++ b/src/encoding/json/encode.go @@ -718,14 +718,22 @@ func encodeByteSlice(e *encodeState, v reflect.Value, _ encOpts) { } s := v.Bytes() e.WriteByte('"') - if len(s) < 1024 { - // for small buffers, using Encode directly is much faster. - dst := make([]byte, base64.StdEncoding.EncodedLen(len(s))) + encodedLen := base64.StdEncoding.EncodedLen(len(s)) + if encodedLen <= len(e.scratch) { + // If the encoded bytes fit in e.scratch, avoid an extra + // allocation and use the cheaper Encoding.Encode. + dst := e.scratch[:encodedLen] + base64.StdEncoding.Encode(dst, s) + e.Write(dst) + } else if encodedLen <= 1024 { + // The encoded bytes are short enough to allocate for, and + // Encoding.Encode is still cheaper. + dst := make([]byte, encodedLen) base64.StdEncoding.Encode(dst, s) e.Write(dst) } else { - // for large buffers, avoid unnecessary extra temporary - // buffer space. + // The encoded bytes are too long to cheaply allocate, and + // Encoding.Encode is no longer noticeably cheaper. enc := base64.NewEncoder(base64.StdEncoding, e) enc.Write(s) enc.Close() |