add async io writer

README.md

@@ -16,8 +16,6 @@
     - `AsyncWriter`, *asynchronously & performant*
     - `MultiLevelWriter`, *multiple level dispatch*
     - `SyslogWriter`, *memory efficient syslog*
-   file  - `JournalWriter`, *linux systemd logging*
-    - `EventlogWriter`, *windows system event*
 * Stdlib Log Adapter
     - `Logger.Std`, *transform to std log instances*
     - `Logger.Slog`, *transform to log/slog instances*

async.go

@@ -8,7 +8,7 @@ import (
 	"unsafe"
 )
 
-// AsyncWriter is an Writer that writes asynchronously.
+// AsyncWriter is a Writer that writes asynchronously.
 type AsyncWriter struct {
 	// Writer specifies the writer of output.
 	Writer Writer
@@ -42,6 +42,22 @@ func (w *AsyncWriter) Close() (err error) {
 
 var ErrAsyncWriterFull = errors.New("async writer is full")
 
+var eepool = sync.Pool{
+	New: func() any {
+		return new(Entry)
+	},
+}
+
+// Write implements io.Writer.
+func (w *AsyncWriter) Write(p []byte) (n int, err error) {
+	e := eepool.Get().(*Entry)
+	e.buf = p
+	n, err = w.Writer.WriteEntry(e)
+	e.buf = nil
+	eepool.Put(e)
+	return
+}
+
 // WriteEntry implements Writer.
 func (w *AsyncWriter) WriteEntry(e *Entry) (int, error) {
 	w.once.Do(func() {
@@ -87,3 +103,4 @@ func (w *AsyncWriter) writer() {
 }
 
 var _ Writer = (*AsyncWriter)(nil)
+var _ io.Writer = (*AsyncWriter)(nil)

async_test.go

@@ -118,3 +118,25 @@ func BenchmarkAsyncFileWriter(b *testing.B) {
 		}
 	})
 }
+
+func BenchmarkAsyncIOWriter(b *testing.B) {
+	logger := TSVLogger{
+		Writer: &AsyncWriter{
+			ChannelSize:    4096,
+			WritevDisabled: false,
+			DiscardOnFull:  false,
+			Writer: &FileWriter{
+				Filename: "async_file_test3.log",
+			},
+		},
+	}
+	defer logger.Writer.(io.Closer).Close()
+
+	b.ReportAllocs()
+	b.ResetTimer()
+	b.RunParallel(func(b *testing.PB) {
+		for b.Next() {
+			logger.New().Str("hello file writer").Msg()
+		}
+	})
+}