From 84169c6c55f631b1d7c08bcafa105cff154ebb5e Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Wed, 4 Jul 2018 13:35:44 +0000
Subject: [PATCH 1/2] Use a buffer pool in report.ReadBinary() to reduce
 garbage-collection

---
 report/marshal.go | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/report/marshal.go b/report/marshal.go
index 65921e3c5..74969750b 100644
--- a/report/marshal.go
+++ b/report/marshal.go
@@ -10,6 +10,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
 
 	log "github.com/Sirupsen/logrus"
 	"github.com/ugorji/go/codec"
@@ -61,13 +62,18 @@ func (c byteCounter) Read(p []byte) (n int, err error) {
 	return n, err
 }
 
+// buffer pool to reduce garbage-collection
+var bufferPool = &sync.Pool{
+	New: func() interface{} { return new(bytes.Buffer) },
+}
+
 // ReadBinary reads bytes into a Report.
 //
 // Will decompress the binary if gzipped is true, and will use the given
 // codecHandle to decode it.
 func (rep *Report) ReadBinary(r io.Reader, gzipped bool, codecHandle codec.Handle) error {
 	var err error
-	var compressedSize, uncompressedSize uint64
+	var compressedSize uint64
 
 	// We have historically had trouble with reports being too large. We are
 	// keeping this instrumentation around to help us implement
@@ -82,12 +88,14 @@ func (rep *Report) ReadBinary(r io.Reader, gzipped bool, codecHandle codec.Handl
 		}
 	}
 	// Read everything into memory before decoding: it's faster
-	buf, err := ioutil.ReadAll(r)
+	buf := bufferPool.Get().(*bytes.Buffer)
+	buf.Reset()
+	defer bufferPool.Put(buf)
+	uncompressedSize, err := buf.ReadFrom(r)
 	if err != nil {
 		return err
 	}
-	uncompressedSize = uint64(len(buf))
-	if err := rep.ReadBytes(buf, codecHandle); err != nil {
+	if err := rep.ReadBytes(buf.Bytes(), codecHandle); err != nil {
 		return err
 	}
 	log.Debugf(

From 8e5b19cbcb59b917824abc3bfb95c29f4019359a Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Wed, 4 Jul 2018 14:03:17 +0000
Subject: [PATCH 2/2] Use buffer pool in report.MakeFromBytes() to reduce
 garbage-collection

---
 report/marshal.go | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/report/marshal.go b/report/marshal.go
index 74969750b..1dc7fe52d 100644
--- a/report/marshal.go
+++ b/report/marshal.go
@@ -6,7 +6,6 @@ import (
 	"compress/gzip"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -128,11 +127,13 @@ func MakeFromBytes(buf []byte) (*Report, error) {
 	if err != nil {
 		return nil, err
 	}
-	buf, err = ioutil.ReadAll(r)
+	buffer := bufferPool.Get().(*bytes.Buffer)
+	buffer.Reset()
+	defer bufferPool.Put(buffer)
+	uncompressedSize, err := buffer.ReadFrom(r)
 	if err != nil {
 		return nil, err
 	}
-	uncompressedSize := len(buf)
 	log.Debugf(
 		"Received report sizes: compressed %d bytes, uncompressed %d bytes (%.2f%%)",
 		compressedSize,
@@ -140,7 +141,7 @@ func MakeFromBytes(buf []byte) (*Report, error) {
 		float32(compressedSize)/float32(uncompressedSize)*100,
 	)
 	rep := MakeReport()
-	if err := rep.ReadBytes(buf, &codec.MsgpackHandle{}); err != nil {
+	if err := rep.ReadBytes(buffer.Bytes(), &codec.MsgpackHandle{}); err != nil {
 		return nil, err
 	}
 	return &rep, nil