Abstract: Techniques are disclosed for workflow based high availability analysis in computing systems. For example, a computer-implemented method for analyzing an information network infrastructure to identify one or more availability weak points includes the following steps. A workflow specification is provided based on one or more user-visible processes and an application topology. Service workflows associated with the specification are mapped from the application topology to the infrastructure to generate a workflow data structure. An availability weak point analysis is performed in accordance with the workflow data structure to determine one or more optimal high availability parameters for one or more deployed components of the infrastructure. The one or more optimal high availability parameters are applied in the infrastructure so as to substantially eliminate the one or more availability weak points.

Abstract: A method, device and system for generating an HA group according to a user's HA requirement by retrieving an applicable HA pattern, according to a result of HA requirement analysis on the user's HA requirement; generating an initial HA group based on the retrieved HA pattern; performing context rebuilding on a member unit in the initial HA group to obtain a preliminarily configured HA group; generating a member unit based HA group variant for the preliminarily configured HA group according to an HA group redundancy obtained from the user's HA requirement; and performing structure configuration and attribute configuration on a member unit in the generated HA group variant to obtain an HA group that meets the user's HA requirement.

Abstract: A method, system, and computer program product are disclosed for automatically determining a valid ordering of provisioning operations, and their needed parameters, so that a provisioning system can configure a desired resource state. This is accomplished by formally describing the pre-conditions and effects of provisioning operations, the current state of managed resources and the desired final state. A planning algorithm is then used to determine the provisioning operations, a valid ordering and appropriate parameters to bring the system from the current state to the desired state.

Abstract: A method, device and system for generating an HA group according to a user's HA requirement by retrieving an applicable HA pattern, according to a result of HA requirement analysis on the user's HA requirement; generating an initial HA group based on the retrieved HA pattern; performing context rebuilding on a member unit in the initial HA group to obtain a preliminarily configured HA group; generating a member unit based HA group variant for the preliminarily configured HA group according to an HA group redundancy obtained from the user's HA requirement; and performing structure configuration and attribute configuration on a member unit in the generated HA group variant to obtain an HA group that meets the user's HA requirement.

Abstract: Techniques are disclosed for workflow based high availability analysis in computing systems. For example, a computer-implemented method for analyzing an information network infrastructure to identify one or more availability weak points includes the following steps. A workflow specification is provided based on one or more user-visible processes and an application topology. Service workflows associated with the specification are mapped from the application topology to the infrastructure to generate a workflow data structure. An availability weak point analysis is performed in accordance with the workflow data structure to determine one or more optimal high availability parameters for one or more deployed components of the infrastructure. The one or more optimal high availability parameters are applied in the infrastructure so as to substantially eliminate the one or more availability weak points.

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: The number of instances of an application running in a computing environment are controlled by monitoring the current load on the application, and altering the current number of instances of the application based on results of the monitoring. The load may be monitored by monitoring the current number of instances of the application running in the computing environment. Where a maximum, minimum and/or initial number on startup, of instances of the application are specified, the altering is done based on comparing the current number to one or more of the specified numbers of instances.

Abstract: Resources are checkpointed in order to save the state of the resources. The resources can then be brought back to the same running state, during a restart procedure, by making use of the saved state. The determination of when to take a checkpoint or when to restart a resource is made by an entity, such as a cluster manager, external to the entity initiating or taking the checkpoint or performing the restart. The decision to checkpoint/restart a resource is provided by the cluster manager to a resource manager associated with the resource. This communication is facilitated by interfaces to the cluster manager provided by the resource manager.

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 method and program product for managing membership of process groups of a distributed computing environment. Requests to alter membership of a first process group are received and presented to the first process group as a batched request. However, requests to change the membership of a second process group are received and presented to the second process group serially. Thus, the manner in which requests are presented can be different for various process groups. Additionally, different types of requests can be presented to the same process group in a differing manner. For instance, requests to join a process group can be presented as a batched request and requests to leave the process group can be presented serially, or vice versa.

Abstract: A barrier synchronization system in a distributed computing environment. A group of members, including a plurality of related processes executing on one or more processors of the distributed computing environment, is provided a protocol having a dynamic number of synchronization phases. The protocol is voted on by one or more members of the group to determine how the protocol should proceed for the group of members. The protocol may complete successfully, continue to another synchronization phase or be rejected. The group of members determines how many synchronization phases the protocol is to include.

Abstract: 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 barrier synchronization program product in a distributed computing environment. A group of members, including a plurality of related processes executing on one or more processors of the distributed computing environment, is provided a protocol having a dynamic number of synchronization phases. The protocol is voted on by one or more members of the group to determine how the protocol should proceed for the group of members. The protocol may complete successfully, continue to another synchronization phase or be rejected. The group of members determines how many synchronization phases the protocol is to include.

Abstract: Detecting the failure of the name server node and consulting a membership list of nodes in the domain to determine the crown prince (CP) node who is next in line to become the name server. The other available nodes in the domain periodically send recover messages to the CP node, and responsive to receiving the recover messages from all the other available nodes in the domain, the CP node perform a two phase takeover whereby the CP node becomes the name server for managing said processors in the domain. After the CP node becomes the name server, the other available nodes in the domain send data to the new name server necessary for the name server to manage the other available nodes in the domain. All request messages requesting management by the name server are stored locally until after the CP becomes the name server. The locally stored request messages are then processed by the other available nodes such that no request messages are lost during recovery.

Abstract: Managing membership of a domain of processors in a distributed computing environment including determining the lowest numbered node available in the domain and periodically sending grovel messages from the other available nodes to the lowest numbered node in the domain. Responsive to receiving all of the grovel messages by the lowest numbered node, the lowest numbered node performs a two phase commit whereby the lowest numbered node becomes a name server for managing the processors in the domain. The two phase commit includes sending an insert phase 1 (P1) message to the other available nodes from the lowest numbered node and, responsive to the insert P1 message, sending an acknowledge (ACK) message from the other available nodes to the lowest numbered node. Responsive to the ACK messages, a commit message is sent to the other available nodes notifying them that the lowest numbered node has become the name server.

Abstract: Recovery of a name server managing membership of a domain of processors in a distributed computing environment which includes detecting the failure of the name server node and consulting a membership list of nodes in the domain to determine the crown prince (CP) node who is next in line to become the name server. The other available nodes in the domain periodically send recover messages to the CP node, and responsive to receiving the recover messages from all the other available nodes in the domain, the CP node perform a two phase takeover whereby the CP node becomes the name server for managing said processors in the domain. After the CP node becomes the name server, the other available nodes in the domain send data to the new name server necessary for the name server to manage the other available nodes in the domain. All request messages requesting management by the name server are stored locally until after the CP becomes the name server.

Abstract: In a distributed computing environment having a plurality of groups of processors, each processor group maintains its own set of ordered messages. A message is sent to a group of processors. In particular, a request to multicast a message is sent to a leader of the group of processors, i.e., a group leader, and the group leader assigns a sequence number to the message to be sent, thereby providing an ordered message. Then, the group leader multicasts the ordered message to the group of processors. When the processors of the group receive the ordered message, each determines whether the message is in proper sequence order. If the message is out of order for a particular processor indicating that a message has been missed, then that particular processor requests the missing message from a processor within the group.

Abstract: System managing membership of a group of processors in a distributed computing environment. Specific actions are identified and performed in order to manage the group membership. A processor requests to join the group of processors and thus, is added to the group. Similarly, processors may request to leave the group or may fail and then are removed from the group. The group of members also receives multicasts initiated from one member of the group to other members of the group. Additionally, each group of processors within a distributed computing environment has a group leader that controls the actions being performed for the group of members.

Abstract: In a distributed computing environment having a plurality of groups of processors, each processor group maintains its own set of ordered messages. A message is sent to a group of processors. In particular, a request to multicast a message is sent to a leader of the group of processors, i.e., a group leader, and the group leader assigns a sequence number to the message to be sent, thereby providing an ordered message. Then, the group leader multicasts the ordered message to the group of processors. When the processors of the group receive the ordered message, each determines whether the message is in proper sequence order. If the message is out of order for a particular processor indicating that a message has been missed, then that particular processor requests the missing message from a processor within the group.

Abstract: Managing group events by a name server for a group of processors in a distributed computing environment by receiving a message by said name server from one of the nodes requesting an event, determining what event is being requested by the message, determining which group the event is for, and storing an identification of the requesting node in an interested party set for the group. The name server determines if the group has a group leader, and if the group does not have a group leader, stores the event to be performed responsive to the message in a lookup queue to be processed when a group leader has been established. The first node requesting an event for a group is established by the name server as the group leader. The state of the group may have a first state wherein no group is established, a second state wherein the group is established but has no group leader, or a third state wherein the group is established and the group has a group leader.