[vegz] Add simple sync.Pool task.

This commit is contained in:
Arseny Balobanov 2022-05-05 19:08:49 +03:00
parent 9c86effadf
commit c975e9ef52
4 changed files with 114 additions and 0 deletions

3
vegz/README.md Normal file
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## vegz [runtime]
В этой задаче нужно победить бенчмарк, переписав функцию сериализации в `gzip`.

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vegz/encode.go Normal file
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//go:build !solution
package vegz
import (
"compress/gzip"
"io"
)
func Encode(data []byte, w io.Writer) error {
ww := gzip.NewWriter(w)
defer func() { _ = ww.Close() }()
if _, err := ww.Write(data); err != nil {
return err
}
return ww.Flush()
}

63
vegz/encode_test.go Normal file
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package vegz
import (
"bytes"
"compress/gzip"
"io"
"testing"
"github.com/stretchr/testify/require"
"gitlab.com/slon/shad-go/tools/testtool"
)
func BenchmarkEncode(b *testing.B) {
data := []byte(
"New function should generally only return pointer types, " +
"since a pointer can be put into the return interface " +
"value without an allocation. " +
testtool.RandomName(),
)
b.ResetTimer()
b.ReportAllocs()
for n := 0; n < b.N; n++ {
require.NoError(b, Encode(data, io.Discard))
}
}
func TestRoundTrip(t *testing.T) {
testCases := []struct {
name string
in string
}{
{name: "empty", in: ""},
{name: "simple", in: "A long time ago in a galaxy far, far away..."},
{name: "random", in: testtool.RandomName()},
}
for _, tc := range testCases {
t.Run(tc.name, func(t *testing.T) {
buf := new(bytes.Buffer)
require.NoError(t, Encode([]byte(tc.in), buf))
out, err := decode(buf.Bytes())
require.NoError(t, err, tc.in)
require.Equal(t, tc.in, string(out))
})
}
}
func decode(data []byte) ([]byte, error) {
r, err := gzip.NewReader(bytes.NewReader(data))
if err != nil {
return nil, err
}
buf := &bytes.Buffer{}
if _, err := io.Copy(buf, r); err != nil {
return nil, err
}
return buf.Bytes(), nil
}

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vegz/solution.go Normal file
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//go:build solution
package vegz
import (
"compress/gzip"
"io"
"sync"
)
var writerPool = sync.Pool{
New: func() interface{} {
return new(gzip.Writer)
},
}
func Encode(data []byte, w io.Writer) error {
ww := writerPool.Get().(*gzip.Writer)
defer func() {
_ = ww.Close()
writerPool.Put(ww)
}()
ww.Reset(w)
if _, err := ww.Write(data); err != nil {
return err
}
return ww.Close()
}