Abstract: An improved method and system for performing dynamic online multi-parameter optimization for autonomic computing systems are provided. With the method and system of the present invention, a simplex, i.e. a set of points in the parameter space that has been directly sampled, is maintained. The system's performance with regard to a particular utility value is measured for the particular setting of configuration parameters associated with each point in the simplex. A new sample point is determined using the geometric transformations of the simplex. The method and system provide mechanisms for limiting the size of the simplex that is generated through these geometric transformations so that the present invention may be implemented in noisy environments in which the same configuration settings may lead to different results with regard to the utility value. In addition, mechanisms are provided for resampling a current best point in the simplex to determine if the environment has changed.

Abstract: Techniques for arranging operations performable on information in an information processing system are provided. In a system having a plurality of information producers and a plurality of information subscribers, paths are identified over which information traverses, and within which the information is subject to select and/or transform operations. The present invention optimizes the system by reorganizing the sequence of select and transform operations so that transforms follow select operations; and by combining multiple select and transform operations into single select and transform operations, respectively. Using these optimizations, the processing resources of the system can be reorganized, and/or information flow graphs describing the system can be designed, so that the select operations are “pushed” toward the producers, and transform operations are “pushed” toward the subscribers. Efficient content-based routing systems can then be used to implement the select operations.

Abstract: Techniques for arranging operations performable on information in an information processing system are provided. In a system having a plurality of information producers and a plurality of information subscribers, paths are identified over which information traverses, and within which the information is subject to select and/or transform operations. The present invention optimizes the system by reorganizing the sequence of select and transform operations so that transforms follow select operations; and by combining multiple select and transform operations into single select and transform operations, respectively. Using these optimizations, the processing resources of the system can be reorganized, and/or information flow graphs describing the system can be designed, so that the select operations are “pushed” toward the producers, and transform operations are “pushed” toward the subscribers. Efficient content-based routing systems can then be used to implement the select operations.

Abstract: A content-based publish/subscribe system for providing gapless message delivery from a publishing client to a subscribing client, the system includes a plurality of brokers operatively coupled to one another via a network. Each of the brokers include at least one processor and are configured as a publisher-hosting broker, a subscriber-hosting broker or an intermediate broker. The subscriber-hosting broker is operatively coupled to the publisher-hosting broker via the network through the intermediate broker. At least a portion of the plurality of brokers are configured so as to eliminate a need for persistent storage of messages at the intermediate broker and to substantially guarantee a gapless delivery of one or more messages transmitted by the publishing client to the subscribing client, even in the presence of a failure in the publish/subscribe system.

Abstract: Program product for an application programming interface that unifies a plurality of mechanisms into a single framework. The interface includes a mechanism for communicating between members of a process group of related processes, and a mechanism for synchronizing the related processes of the process group. Additionally, the application programming interface may include mechanisms for managing membership of the process group or a processor group of processors, and/or a mechanism for controlling a group state value for the process group.

Abstract: A multinode, multicast communications network has a distributed control for the creation, administration and operational mode selection operative in each of the nodes of the network. Each node is provided with a Set Manager for controlling either creation of, administration or access to a set of users to whom a multicast is to be directed. The Set Manager maintains a record of the local membership of all users associated with the node in which the Set Manager resides. A given Set Manager for each designated set of users is assigned the task of being the Set Leader to maintain membership information about the entire set of users in the multicast group. One of the Set Managers in the communications network is designated to be the Registrar which maintains a list of all the Set Leaders in the network. The Registrar insures that there is one and only one Set Leader for each set of users, answers inquiries about the membership of the sets and directs inquiries to appropriate Set Leaders if necessary.

Abstract: Method and apparatus for managing internal-node communications in a packet switching network by calculating optimal routes for packets and addressing subnodes within packet nodes using a specific message format. Internal communication facilities called intranode links connect multiple subnodes within nodes. Each subnode contains a switching mechanism and routes packet to other nodes, subnodes, or user applications using a specific message format. The message format allows specific subnodes anywhere in the network to the addressed by any other subnode, making communications more efficient and simplifying the management of internode links.

Abstract: A packet communications network in which multicast transmissions are made reliable by transmitting acknowledgements to all neighbors of every receiving node, including the source node. This allows the relinquishment of message holding buffers as soon as all near neighbors acknowledge receipt of the message after only tile longest round trip time to the nearest neighbors, rather than the round trip to the furthest destination. Moreover, highly reliable ancillary point-to-point transmission facilities can be used to retransmit multicast messages indicated as being lost by failure of acknowledgment. Finally, network partitions occurring during the multicast procedure do not necessarily lose the multicast message to the remote partitions since any node receiving the message can insure delivery to all other nodes in that partition.

Abstract: Method and apparatus for making limited internal-node communication facilities externally visible in a packet switching network. Internal-node communication facilities are called intranode links, can include any cable, channel, bus, etc. over which data passes, and are used to connect the multiple subnodes within a given node. Each subnode contains a switching mechanism and routes packets to other nodes, subnodes, or user applications. Each node provides network control functions such as topology, directory, path selection, and bandwidth management which can manage intranode links in the same manner that internode links are currently managed.

Abstract: In a multicast network communication system, administration of the communication path making up the multicast tree itself has been separated from control and administration of the network. Creation of a multicast distribution tree and control over the membership thereof, is separately controlled independently from the creation and use of the tree transmission path used to communicate among the members of a multicast set. Transmission distribution trees are set up when a transmission request is received and the properties of the transmission path that is required are known. Transmission paths are created and controlled by all nodes in the communications system, each node having necessary control code and processors for responding to requests from set members to transmit a message to groups of users by creating and activating the necessary tree communication path distribution linkages. A distribution tree is created by the Tree Leader by generating a tree address using a random number generator.

Abstract: A packet communications system provides for point-to-point packet routing and multicast packet routing to limited subsets of nodes in the network, using a routing field in the packet header which is processed according to two different protocols. A third protocol is provided in which a packet can be multicast to the limited subset even when launched from a node which is not a member of the subset. The routing field includes a first portion which contains the route labels necessary to deliver the packet to the multicast subset. A second portion of the routing field contains the multicast subset identifier which can then be used to deliver the packet to all of the members of the multicast subset. Provision is made to backtrack deliver the packet to the last node identified before the multicast subset if that last node is itself a member of the subset.

Abstract: A method and apparatus for dynamically adjusting the window size in a session between a sender and a receiver over a link of a packet transmission network. This invention discloses a dynamic window adjustment scheme to determine the optimum window size with a minimum number of iterations. This invention also covers a method and apparatus for sharing pacing credits among a number of sessions during which packets are transmitted over the network. With this invention sessions having no packets to transmit will send pacing credits to a shared credit pool while pacing credits will be distributed to those session having packets to transmit.

Abstract: A method for reducing transmission polling overhead of packets within a node of a communications network. This invention involves setting session ready bits in the line adaptor modules of the node. These bits are then used to inform a given module as to which modules of the node have packets that are bound for the given module. A given module of the node will not transmit a pacing message (YT control message) to another module unless it knows that the other module has a packet to transmit to the given module.