sync.Pool

04-sync-package/06-sync-pool/main.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+ "bytes"
+ "fmt"
+ "io"
+ "os"
+ "sync"
+ "time"
+)
+
+// create pool of bytes.Buffers which can be reused.
+var bufPool = sync.Pool{
+ New: func() interface{} {
+ fmt.Println("Allocating new bytes.Buffer")
+ return new(bytes.Buffer)
+ },
+}
+
+func log(w io.Writer, val string) {
+ // var b bytes.Buffer
+ b := bufPool.Get().(*bytes.Buffer)
+ b.Reset()
+
+ b.WriteString(time.Now().Format("15:04:05"))
+ b.WriteString(" : ")
+ b.WriteString(val)
+ b.WriteString("\n")
+
+ _, _ = w.Write(b.Bytes())
+
+ bufPool.Put(b)
+}
+
+func main() {
+ log(os.Stdout, "debug-string1")
+ log(os.Stdout, "debug-string2")
+}