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moby--moby/pkg/ioutils/bytespipe_test.go
Brian Goff 9a25b1d942 Improve performance/reduce allocs of bytespipe
Creates a `fixedBuffer` type that is used to encapsulate functionality
for reading/writing from the underlying byte slices.

Uses lazily-loaded set of sync.Pools for storing buffers that are no
longer needed so they can be re-used.

```
benchmark                     old ns/op     new ns/op     delta
BenchmarkBytesPipeWrite-8     138469        48985         -64.62%
BenchmarkBytesPipeRead-8      130922        56601         -56.77%

benchmark                     old allocs     new allocs     delta
BenchmarkBytesPipeWrite-8     18             8              -55.56%
BenchmarkBytesPipeRead-8      0              0              +0.00%

benchmark                     old bytes     new bytes     delta
BenchmarkBytesPipeWrite-8     66903         1649          -97.54%
BenchmarkBytesPipeRead-8      0             1             +Inf%
```

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2016-04-05 13:06:04 -04:00

159 lines
3.5 KiB
Go

package ioutils
import (
"crypto/sha1"
"encoding/hex"
"math/rand"
"testing"
"time"
)
func TestBytesPipeRead(t *testing.T) {
buf := NewBytesPipe()
buf.Write([]byte("12"))
buf.Write([]byte("34"))
buf.Write([]byte("56"))
buf.Write([]byte("78"))
buf.Write([]byte("90"))
rd := make([]byte, 4)
n, err := buf.Read(rd)
if err != nil {
t.Fatal(err)
}
if n != 4 {
t.Fatalf("Wrong number of bytes read: %d, should be %d", n, 4)
}
if string(rd) != "1234" {
t.Fatalf("Read %s, but must be %s", rd, "1234")
}
n, err = buf.Read(rd)
if err != nil {
t.Fatal(err)
}
if n != 4 {
t.Fatalf("Wrong number of bytes read: %d, should be %d", n, 4)
}
if string(rd) != "5678" {
t.Fatalf("Read %s, but must be %s", rd, "5679")
}
n, err = buf.Read(rd)
if err != nil {
t.Fatal(err)
}
if n != 2 {
t.Fatalf("Wrong number of bytes read: %d, should be %d", n, 2)
}
if string(rd[:n]) != "90" {
t.Fatalf("Read %s, but must be %s", rd, "90")
}
}
func TestBytesPipeWrite(t *testing.T) {
buf := NewBytesPipe()
buf.Write([]byte("12"))
buf.Write([]byte("34"))
buf.Write([]byte("56"))
buf.Write([]byte("78"))
buf.Write([]byte("90"))
if buf.buf[0].String() != "1234567890" {
t.Fatalf("Buffer %q, must be %q", buf.buf[0].String(), "1234567890")
}
}
// Write and read in different speeds/chunk sizes and check valid data is read.
func TestBytesPipeWriteRandomChunks(t *testing.T) {
cases := []struct{ iterations, writesPerLoop, readsPerLoop int }{
{100, 10, 1},
{1000, 10, 5},
{1000, 100, 0},
{1000, 5, 6},
{10000, 50, 25},
}
testMessage := []byte("this is a random string for testing")
// random slice sizes to read and write
writeChunks := []int{25, 35, 15, 20}
readChunks := []int{5, 45, 20, 25}
for _, c := range cases {
// first pass: write directly to hash
hash := sha1.New()
for i := 0; i < c.iterations*c.writesPerLoop; i++ {
if _, err := hash.Write(testMessage[:writeChunks[i%len(writeChunks)]]); err != nil {
t.Fatal(err)
}
}
expected := hex.EncodeToString(hash.Sum(nil))
// write/read through buffer
buf := NewBytesPipe()
hash.Reset()
done := make(chan struct{})
go func() {
// random delay before read starts
<-time.After(time.Duration(rand.Intn(10)) * time.Millisecond)
for i := 0; ; i++ {
p := make([]byte, readChunks[(c.iterations*c.readsPerLoop+i)%len(readChunks)])
n, _ := buf.Read(p)
if n == 0 {
break
}
hash.Write(p[:n])
}
close(done)
}()
for i := 0; i < c.iterations; i++ {
for w := 0; w < c.writesPerLoop; w++ {
buf.Write(testMessage[:writeChunks[(i*c.writesPerLoop+w)%len(writeChunks)]])
}
}
buf.Close()
<-done
actual := hex.EncodeToString(hash.Sum(nil))
if expected != actual {
t.Fatalf("BytesPipe returned invalid data. Expected checksum %v, got %v", expected, actual)
}
}
}
func BenchmarkBytesPipeWrite(b *testing.B) {
testData := []byte("pretty short line, because why not?")
for i := 0; i < b.N; i++ {
readBuf := make([]byte, 1024)
buf := NewBytesPipe()
go func() {
var err error
for err == nil {
_, err = buf.Read(readBuf)
}
}()
for j := 0; j < 1000; j++ {
buf.Write(testData)
}
buf.Close()
}
}
func BenchmarkBytesPipeRead(b *testing.B) {
rd := make([]byte, 512)
for i := 0; i < b.N; i++ {
b.StopTimer()
buf := NewBytesPipe()
for j := 0; j < 500; j++ {
buf.Write(make([]byte, 1024))
}
b.StartTimer()
for j := 0; j < 1000; j++ {
if n, _ := buf.Read(rd); n != 512 {
b.Fatalf("Wrong number of bytes: %d", n)
}
}
}
}