Tune the following ORB parameters using the Admin Console:
Max Message Fragment Size: Messages larger than this number of bytes will be fragmented. In CORBA GIOPv1.2, a Request, Reply, LocateRequest and LocateReply message can be broken into multiple fragments. The first message is a regular Request or Reply message with more fragments bit in the flags field set to true. If inter-ORB messages are for the most part larger than the default size (1024 bytes), increase the fragment size to decrease latencies on the network.
Total Connections: Maximum number of incoming connections at any time, on all listeners. Protects the server state by allowing finite number of connections. This value equals the maximum number of threads that will actively read from the connection.