Memory optimizations for direct mode

proxy/direct.go

@@ -13,6 +13,15 @@ import (
 
 const directPipeBufferSize = 1024 * 1024
 
+var (
+	directPipePool = sync.Pool{
+		New: func() interface{} {
+			rv := make([]byte, directPipeBufferSize)
+			return &rv
+		},
+	}
+)
+
 func directConnection(request *protocol.TelegramRequest) error {
 	telegramConnRaw, err := obfuscated2.TelegramProtocol(request)
 	if err != nil {
@@ -42,8 +51,10 @@ func directPipe(dst io.WriteCloser, src io.ReadCloser, wg *sync.WaitGroup, logge
 		wg.Done()
 	}()
 
-	buf := make([]byte, directPipeBufferSize)
-	if _, err := io.CopyBuffer(dst, src, buf); err != nil {
+	buf := directPipePool.Get().(*[]byte)
+	defer directPipePool.Put(buf)
+
+	if _, err := io.CopyBuffer(dst, src, *buf); err != nil {
 		logger.Debugw("Cannot pump sockets", "error", err)
 	}
 }