code: def _tune(self, args):
          
          self.channel_max = args.read_short() or self.channel_max
          self.frame_max = args.read_long() or self.frame_max
          self.method_writer.frame_max = self.frame_max
          self.heartbeat = args.read_short()
  
          self._x_tune_ok(self.channel_max, self.frame_max, 0)
docs: propose connection tuning parameters
  
          This method proposes a set of connection configuration values
          to the client.  The client can accept and/or adjust these.
  
          PARAMETERS:
              channel_max: short
  
                  proposed maximum channels
  
                  The maximum total number of channels that the server
                  allows per connection. Zero means that the server does
                  not impose a fixed limit, but the number of allowed
                  channels may be limited by available server resources.
  
              frame_max: long
  
                  proposed maximum frame size
  
                  The largest frame size that the server proposes for
                  the connection. The client can negotiate a lower
                  value.  Zero means that the server does not impose any
                  specific limit but may reject very large frames if it
                  cannot allocate resources for them.
  
                  RULE:
  
                      Until the frame-max has been negotiated, both
                      peers MUST accept frames of up to 4096 octets
                      large. The minimum non-zero value for the frame-
                      max field is 4096.
  
              heartbeat: short
  
                  desired heartbeat delay
  
                  The delay, in seconds, of the connection heartbeat
                  that the server wants.  Zero means the server does not
                  want a heartbeat.