Abstract: A method, system and program product for managing resources among a plurality of nodes in a computing environment. An exemplary method includes the operations of collecting information about the resources and their associations with the nodes, making such information available to the other nodes, and reiterating these operations, resulting in maintaining current local and global views for nodes of the resources and providing a method of controlling usage of resources.

Abstract: The notion of controlling, using and monitoring remote resources in a distributed data processing system through the use of proxy resource managers and agents is extended to provide failover capability so that resource coverage is preserved and maintained even in the event of either temporary or longer duration node failure. Mechanisms are provided for consistent determination of resource status. Mechanisms are also provided which facilitate the joining of nodes to a group of nodes while still preserving remote resource operations. Additional mechanisms are also provided for the return of remote resource management to the control of a previously failed, but now recovered node, even if the failure had resulted in a node reset.

Abstract: A distributed system has a multiplicity of nodes. A group of the nodes subscribe to a group services process. The group is subject to dissolving. A list of persistent subscribers to the group is maintained. Subscriptions to members and states of the group that are persistent subscribers do not terminate in response to the group being dissolved. The persistent subscribers automatically receive a notice in response to the group being reestablished and do not need to re-subscribe to the group.

Abstract: A method for dispersing scattered information in a coordinated fashion in a distributed computing system having a plurality of nodes where at least two of the nodes are members of a group. The method includes receiving a proposal for a protocol from one of the nodes and sending a request to at least one member of the group of nodes for additional proposals. The method also includes receiving at least one additional proposal in response to the request and sending the proposal and the at least one additional proposal to members of the group at substantially the same time.

Abstract: The notion of controlling, using and monitoring remote resources in a distributed data processing system through the use of proxy resource managers and agents is extended to provide failover capability so that resource coverage is preserved and maintained even in the event of either temporary or longer duration node failure. Mechanisms are provided for consistent determination of resource status. Mechanisms are also provided which facilitate the joining of nodes to a group of nodes while still preserving remote resource operations. Additional mechanisms are also provided for the return of remote resource management to the control of a previously failed, but now recovered node, even if the failure had resulted in a node reset.

Abstract: The notion of controlling, using and monitoring remote resources in a distributed data processing system through the use of proxy resource managers and agents is extended to provide failover capability so that resource coverage is preserved and maintained even in the event of either temporary or longer duration node failure. Mechanisms are provided for consistent determination of resource status. Mechanisms are also provided which facilitate the joining of nodes to a group of nodes while still preserving remote resource operations. Additional mechanisms are also provided for the return of remote resource management to the control of a previously failed, but now recovered node, even if the failure had resulted in a node reset.

Abstract: Syndrome values are employed as a mechanism for synchronization and consistency in a distributed data processing environment. Syndromes are computed for local resources on individual peer nodes and an aggregate syndrome is computed from the individual syndromes. This renders it easy to determine not only that a change has occurred but it also makes it easy to determine which node needs to be updated and thus avoids the needless transmission of updated contents.

Abstract: A system and method for controlling log files is provided in which each log file entry is associated with an importance level. Depending on the importance level, the log entry is stored in a separately maintained set of files which can thus be rotated on different schedules so that the more important log file entries are retained for appropriately longer periods of time so as to be better able to reconstruct event histories and reports for important events.

Abstract: A desired group of reachable nodes of a communications environment is provided. The desired group of reachable nodes includes one or more nodes that can communicate with one another via a same network of a plurality of networks of the communications environment. In one embodiment, the desired group of reachable nodes includes the largest set of nodes that can communicate with one another via a common network. A globally consistent view of this largest set of reachable nodes is provided to interested nodes of the communications environment.

Abstract: In a distributed peer-to-peer data processing system, consistency and access to a global resource maintained on one of the nodes is provided through the use of global incarnation numbers, local incarnation numbers, and proposed incarnation numbers. Internode traffic is kept to a minimum while still maintaining consistency. The system and method of the present invention are particularly useful at start-up and data change processing points in time.

Abstract: In a multinode data processing system, the messages to be transmitted from node to node, per the request of an application program, are stored in a queue on one of the nodes. Acknowledgment of the receipt of the messages is used to control transmission of messages at future times by adjusting the maximum number of allowable messages to be sent from the queue and also by adjusting the time interval that the system waits before retransmitting unacknowledged messages. This permits the use of so-called “unreliable” messaging protocols and relieves application programs and programmers from the burden of employing more complicated protocols.

Abstract: The notion of controlling, using and monitoring remote resources in a distributed data processing system through the use of proxy resource managers and agents is extended to provide failover capability so that resource coverage is preserved and maintained even in the event of either temporary or longer duration node failure. Mechanisms are provided for consistent determination of resource status. Mechanisms are also provided which facilitate the joining of nodes to a group of nodes while still preserving remote resource operations. Additional mechanisms are also provided for the return of remote resource management to the control of a previously failed, but now recovered node, even if the failure had resulted in a node reset.

Abstract: Proxy Resource Managers are deployed on data processing nodes having full resource management support. Proxy Resource Agents are deployed on remote nodes without this support. The status and attributes of a wide range of resources are kept consistent through the use of a system-wide Resource Generation Number whose initiation and maintenance is coordinated through communications between the Proxy Resource Manager and the Proxy Resource Agent. Resources managed and controlled herein include files, programs, devices and entire compute nodes.

Abstract: Syndrome values are employed as a mechanism for synchronization and consistency in a distributed data processing environment. Syndromes are computed for local resources on individual peer nodes and an aggregate syndrome is computed from the individual syndromes. This renders it easy to determine not only that a change has occurred but it also makes it easy to determine which node needs to be updated and thus avoids the needless transmission of updated contents.

Abstract: In a multinode data processing system, the messages to be transmitted from node to node, per the request of an application program, are stored in a queue on one of the nodes. Acknowledgment of the receipt of the messages is used to control transmission of messages at future times by adjusting the maximum number of allowable messages to be sent from the queue and also by adjusting the time interval that the system waits before retransmitting unacknowledged messages. This permits the use of so-called “unreliable” messaging protocols and relieves application programs and programmers from the burden of employing more complicated protocols.

Abstract: A system and method for controlling log files is provided in which each log file entry is associated with an importance level. Depending on the importance level, the log entry is stored in a separately maintained set of files which can thus be rotated on different schedules so that the more important log file entries are retained for appropriately longer periods of time so as to be better able to reconstruct event histories and reports for important events.

Abstract: A desired group of reachable nodes of a communications environment is provided. The desired group of reachable nodes includes one or more nodes that can communicate with one another via a same network of a plurality of networks of the communications environment. In one embodiment, the desired group of reachable nodes includes the largest set of nodes that can communicate with one another via a common network. A globally consistent view of this largest set of reachable nodes is provided to interested nodes of the communications environment.

Abstract: In a distributed peer-to-peer data processing system, consistency and access to a global resource maintained on one of the nodes is provided through the use of global incarnation numbers, local incarnation numbers, and proposed incarnation numbers. Internode traffic is kept to a minimum while still maintaining consistency. The system and method of the present invention are particularly useful at start-up and data change processing points in time.