Abstract: Described herein are systems, methods, and software to deploy instant guest clusters in a computing environment. In one example, a host is configured to initiate startup operations of a first virtual machine and stop the startup operations prior to performing guest customization operations. The host is further configured to, in response to a request for a second virtual machine, initiate the second virtual machine as an instant clone of the first virtual machine and execute the guest customization operations for the second virtual machine based on metadata provided for the second virtual machine, wherein the metadata provides configuration information for the second virtual machine.

Abstract: In one set of embodiments, during an initial pre-copying phase, copies of the virtual disks of a VM or VM template can be distributed across one or more datastores, prior to the start of any cloning. This effectively seeds each datastore with a disk pool comprising a certain number of copies of the VM/VM template's virtual disks. Then, at the time of receiving a user request to create k clones from the VM/VM template, up to k copies of the VM/VM template's virtual disks that already reside in the disk pools of one or more target datastores can be moved from those disk pools to the clones' home folders on the target datastores, thereby reducing or eliminating the need to create brand new copies of the virtual disks on demand.

Abstract: A method of migrating a network file copy (NFC) operation from a first host computing device to a second host computing device includes the steps of: transmitting a first request to the first host computing device to execute the NFC operation, wherein the NFC operation comprises transferring data from a shared datastore to another datastore; after transmitting the first request, selecting the second host computing device to complete the NFC operation in place of the first host computing device, and transmitting a second request to the first host computing device to stop executing the NFC operation; after transmitting the second request, detecting a message indicating that the first host computing device completed the copying of a first portion of the data; and in response to the detection of the message, transmitting a third request to the second host computing device to perform the remainder of the NFC operation.

Abstract: A method of migrating a network file copy (NFC) operation from a first host computing device to a second host computing device includes the steps of: transmitting a first request to the first host computing device to execute the NFC operation, wherein the NFC operation comprises transferring data from a shared datastore to another datastore; after transmitting the first request, selecting the second host computing device to complete the NFC operation in place of the first host computing device, and transmitting a second request to the first host computing device to stop executing the NFC operation; after transmitting the second request, detecting a message indicating that the first host computing device completed the copying of a first portion of the data; and in response to the detection of the message, transmitting a third request to the second host computing device to perform the remainder of the NFC operation.

Abstract: Methods, apparatus, and products are disclosed for synchronizing an active feed adapter and a backup feed adapter in a high speed, low latency data communications environment that include brokering, by a stream administration server, establishment of an active message stream to a subscribing client device from an active feed adapter, the active message stream capable of communicating active application messages; brokering, by the server, establishment of a backup message stream to the client device from a backup feed adapter, the backup message stream capable of communicating backup application messages; receiving an active feed adapter state in backup messaging middleware of the backup adapter from active messaging middleware of the active adapter; determining, by the backup feed adapter, whether a backup feed adapter state is synchronized with the active feed adapter state; and administering, by the backup feed adapter, operation of the backup adapter in dependence upon the determining.

Abstract: A method includes receiving active application messages that are part of an active message stream in a subscribing client device from an active feed adapter. Each active application message is characterized by an active source stream identifier, an active source stream sequence number, and an active message sequence number. The method includes receiving, in response to a failover from the active feed adapter to a backup feed adapter, backup application messages in the subscribing client device from the backup feed adapter. Each backup application message is characterized by a backup source stream identifier, a backup source stream sequence number, and a backup message sequence number. The method includes administering, by the subscribing client device, the backup application messages in dependence upon the active stream source identifier, the active stream source sequence number, the backup stream source identifier, and the backup stream source sequence number.

Abstract: A group communication service maintains synchronization limiting the group to the processing entities that receive a plurality of source message streams from sources outside the group and transmit delivery message streams to destinations that are outside the group. Synchronization of message ordering and other state synchronization directives are communicated from a leader exclusively to other group members. Once having declared themselves to be synchronized and active by a reply protocol message, which is an opaque object and is interpreted by an application layer, the processing entities independently process the source message streams in accordance with the order specified in the directives, without requiring additional sequencing information from another processing entity.

Abstract: A group communication service is adapted for multi-point to multi-point communication. Identical message streams are received by a tier of processing servers from a tier of sources. The processing servers deliver the message streams to a tier of destinations. The group communication service enables the processing servers to deal with newly added message streams and deleted message streams while preserving total ordering.

Abstract: A method includes receiving active application messages that are part of an active message stream in a subscribing client device from an active feed adapter. Each active application message is characterized by an active source stream identifier, an active source stream sequence number, and an active message sequence number. The method includes receiving, in response to a failover from the active feed adapter to a backup feed adapter, backup application messages in the subscribing client device from the backup feed adapter. Each backup application message is characterized by a backup source stream identifier, a backup source stream sequence number, and a backup message sequence number. The method includes administering, by the subscribing client device, the backup application messages in dependence upon the active stream source identifier, the active stream source sequence number, the backup stream source identifier, and the backup stream source sequence number.

Abstract: Methods, apparatus, and products are disclosed for reliable messaging using redundant message streams in a high speed, low latency data communications environment that include brokering, by a stream administration server, establishment of an active message stream to a subscribing client device from an active feed adapter, the active message stream capable of communicating active application messages; brokering, by the server, establishment of a backup message stream to the subscribing client device from a backup feed adapter, the backup message stream capable of communicating backup application messages representing duplicates of the active messages; receiving the active messages in messaging middleware of the subscribing client device; receiving, in response to a failover, the backup messages in the messaging middleware; and administering, by the messaging middleware, the backup messages in dependence upon an active stream source identifier, an active stream source sequence number, a backup stream source ide

Abstract: Methods and systems are provided in a group communication system for dynamically changing a version of a group communication protocol from a first version to a second version transparently to external sources and destinations. The system accommodates newly joining members that can only support versions of the protocol other than the version currently in use without interruption in service. Similarly, the system can upgrade its operating version of the group communication protocol to improve performance when a member having relatively low capabilities exits the group.

Abstract: A group communication service is adapted for multi-point to multi-point communication. Identical message streams are received by a tier of processing servers from a tier of sources. The processing servers deliver the message streams to a tier of destinations. The group communication service enables the processing servers to deal with newly added message streams and deleted message streams while preserving total ordering.

Abstract: A group communication service maintains synchronization limiting the group to the processing entities that receive a plurality of source message streams from sources outside the group and transmit delivery message streams to destinations that are outside the group. Synchronization of message ordering and other state synchronization directives are communicated from a leader exclusively to other group members. Once having declared themselves to be synchronized and active by a reply protocol message, which is an opaque object and is interpreted by an application layer, the processing entities independently process the source message streams in accordance with the order specified in the directives, without requiring additional sequencing information from another processing entity.

Abstract: Methods and systems are provided in a group communication system for dynamically changing a version of a group communication protocol from a first version to a second version transparently to external sources and destinations. The system accommodates newly joining members that can only support versions of the protocol other than the version currently in use without interruption in service. Similarly, the system can upgrade its operating version of the group communication protocol to improve performance when a member having relatively low capabilities exits the group.

Abstract: A computer-implemented method for communication includes receiving over a network multiple ordered sequences of messages. Multiple processing threads are allocated for processing the received messages. Upon receiving each new message from the network, an ordered sequence to which the new message belongs is identified. While there is at least one preceding message in the identified ordered sequence such that processing, using at least a first processing thread, of the at least one preceding message has not yet been completed, processing of the new message is deferred. Upon completion of the processing of the at least one preceding message using at least the first processing thread, a second processing thread is assigned to process the new message, and the new message is processed using the second processing thread.

Abstract: Methods, apparatus, and products are disclosed for synchronizing an active feed adapter and a backup feed adapter in a high speed, low latency data communications environment that include brokering, by a stream administration server, establishment of an active message stream to a subscribing client device from an active feed adapter, the active message stream capable of communicating active application messages; brokering, by the server, establishment of a backup message stream to the client device from a backup feed adapter, the backup message stream capable of communicating backup application messages; receiving an active feed adapter state in backup messaging middleware of the backup adapter from active messaging middleware of the active adapter; determining, by the backup feed adapter, whether a backup feed adapter state is synchronized with the active feed adapter state; and administering, by the backup feed adapter, operation of the backup adapter in dependence upon the determining.

Abstract: Methods, apparatus, and products are disclosed for reliable messaging using redundant message streams in a high speed, low latency data communications environment that include brokering, by a stream administration server, establishment of an active message stream to a subscribing client device from an active feed adapter, the active message stream capable of communicating active application messages; brokering, by the server, establishment of a backup message stream to the subscribing client device from a backup feed adapter, the backup message stream capable of communicating backup application messages representing duplicates of the active messages; receiving the active messages in messaging middleware of the subscribing client device; receiving, in response to a failover, the backup messages in the messaging middleware; and administering, by the messaging middleware, the backup messages in dependence upon an active stream source identifier, an active stream source sequence number, a backup stream source ide

Abstract: A method and system for detecting deadlock is provided. A second thread monitors a first thread's attempts to lock or release resources in a computing execution environment. A deadlock is detected in response to the second thread determining that the first thread failed to lock or release a resource as expected.

Abstract: A method for eligibility list management in a distributed group membership system, including receiving an eligibility list change request with respect to an eligibility list of a group of computing elements, removing from a view of the group any active members in the group who are to be removed from the eligibility list as indicated by the eligibility list change request, preventing any of the members that are removed from the view from rejoining a view until the eligibility list change is applied to the eligibility list, applying the eligibility list change to the eligibility list, and establishing a new view for any active members in the group who are on the changed eligibility list.