Memory allocation optimizations

buffer.go

@@ -56,7 +56,6 @@ func (b *buffer) fill(need int) (err error) {
 		}
 		return // err
 	}
-	return
 }
 
 // returns next N bytes from buffer.
@@ -72,3 +71,65 @@ func (b *buffer) readNext(need int) (p []byte, err error) {
 	b.length -= need
 	return
 }
+
+// various allocation pools
+
+var bytesPool = make(chan []byte, 16)
+
+// may return unzeroed bytes
+func getBytes(n int) []byte {
+	select {
+	case s := <-bytesPool:
+		if cap(s) >= n {
+			return s[:n]
+		}
+	default:
+	}
+	return make([]byte, n)
+}
+
+func putBytes(s []byte) {
+	select {
+	case bytesPool <- s:
+	default:
+	}
+}
+
+var fieldPool = make(chan []mysqlField, 16)
+
+func getMysqlFields(n int) []mysqlField {
+	select {
+	case f := <-fieldPool:
+		if cap(f) >= n {
+			return f[:n]
+		}
+	default:
+	}
+	return make([]mysqlField, n)
+}
+
+func putMysqlFields(f []mysqlField) {
+	select {
+	case fieldPool <- f:
+	default:
+	}
+}
+
+var rowsPool = make(chan *mysqlRows, 16)
+
+func getMysqlRows() *mysqlRows {
+	select {
+	case r := <-rowsPool:
+		return r
+	default:
+	}
+	return new(mysqlRows)
+}
+
+func putMysqlRows(r *mysqlRows) {
+	*r = mysqlRows{} // zero it
+	select {
+	case rowsPool <- r:
+	default:
+	}
+}

connection.go

@@ -190,13 +190,14 @@ func (mc *mysqlConn) Query(query string, args []driver.Value) (driver.Rows, erro
 			var resLen int
 			resLen, err = mc.readResultSetHeaderPacket()
 			if err == nil {
-				rows := &mysqlRows{mc, false, nil, false}
+				rows := getMysqlRows()
+				rows.mc = mc
 
 				if resLen > 0 {
 					// Columns
 					rows.columns, err = mc.readColumns(resLen)
 				}
-				return rows, err
+				return &mysqlRowsI{rows}, err
 			}
 		}
 
@@ -217,7 +218,8 @@ func (mc *mysqlConn) getSystemVar(name string) (val []byte, err error) {
 		var resLen int
 		resLen, err = mc.readResultSetHeaderPacket()
 		if err == nil {
-			rows := &mysqlRows{mc, false, nil, false}
+			rows := getMysqlRows()
+			rows.mc = mc
 
 			if resLen > 0 {
 				// Columns

errors.go

@@ -24,6 +24,7 @@ var (
 	errPktSync     = errors.New("Commands out of sync. You can't run this command now")
 	errPktSyncMul  = errors.New("Commands out of sync. Did you run multiple statements at once?")
 	errPktTooLarge = errors.New("Packet for query is too large. You can change this value on the server by adjusting the 'max_allowed_packet' variable.")
+	errInvConn     = errors.New("Invalid Connection")
 )
 
 // error type which represents a single MySQL error