Abstract: A plurality of redundant brokers may be used as intermediaries to exchange messages between one or more producers and one or more consumers. More specifically, one or more producers may enqueue messages to a primary broker. The primary broker then dispatches the received messages to one or more interested consumers. However, should the primary broker fail, messages enqueued by the producers may be lost, and thus delivery of such messages may fail. Accordingly, one or more backup brokers may be provided that can assume the responsibilities of the failed primary broker and dispatch copies of the messages that were enqueued by the producers to the failed primary broker.

Abstract: A broker may be used as an intermediary to exchange messages between producers and consumers. The broker may store and dispatch messages from a physical queue stored in a persistent memory. More specifically, the broker may enqueue messages to the physical queue that are received from producers and may dispatch messages from the physical queue to interested consumers. The broker may further utilize one or more logical queues stored in transient memory to track the status of the messages stored in persistent memory. As messages are dispatched to and acknowledged by interested consumers, the broker deletes acknowledged messages from the physical queue. The messages deleted are those preceding a physical ACKlevel pointer that specifies the first non-acknowledged message in the physical queue. The physical ACKlevel pointer is advanced in the physical queue based on the relative position of corresponding logical ACKlevel pointers maintained by the logical queues.

Abstract: The state of a workflow application in a distributed computing environment can be reconstructed by replaying previously executed portions of the workflow application. Embodiments maintain non-serialized event data relating to workflow history and use the data to determine subsequent actions to take in order to advance the workflow. In some embodiments, workflow instances can be serialized in order to create a checkpoint.

Abstract: Various embodiments are disclosed herein including systems and methods for managing the asynchronous and parallel execution of computer programs. Embodiments implement asynchronous execution in a distributed environment. Single-threaded execution of multiple routines can proceed without thread blocking. Asynchronous variable and routine classes are provided to facilitate development of asynchronous systems using substantially the same development techniques as used for synchronous systems. In some embodiments, the systems and methods for managing asynchronous execution of programs are applied to workflow processing systems.

Abstract: Various embodiments are disclosed herein including systems and methods for implementing exception-based error handling in asynchronous, parallel, multi-threaded, and other distributed systems. Embodiments implement exception-based error handling in asynchronous workflow systems, providing try/catch blocks and tree-based cancellation of pending and currently executing activities.

Abstract: A broker may be used as an intermediary to exchange messages between producers and consumers. The broker may store and dispatch messages from a physical queue stored in a persistent memory. More specifically, the broker may enqueue messages to the physical queue that are received from producers and may dispatch messages from the physical queue to interested consumers. The broker may further utilize one or more logical queues stored in transient memory to track the status of the messages stored in persistent memory. As messages are dispatched to and acknowledged by interested consumers, the broker deletes acknowledged messages from the physical queue. The messages deleted are those preceding a physical ACKlevel pointer that specifies the first non-acknowledged message in the physical queue. The physical ACKlevel pointer is advanced in the physical queue based on the relative position of corresponding logical ACKlevel pointers maintained by the logical queues.

Abstract: A broker may be used as an intermediary to exchange messages between producers and consumers. The broker may store and dispatch messages from a physical queue stored in a persistent memory. More specifically, the broker may enqueue messages to the physical queue that are received from producers and may dispatch messages from the physical queue to interested consumers. The broker may further utilize one or more logical queues stored in transient memory to track the status of the messages stored in persistent memory. As messages are dispatched to and acknowledged by interested consumers, the broker deletes acknowledged messages from the physical queue. The messages deleted are those proceeding a physical ACKlevel pointer that specifies the first non-acknowledged message in the physical queue. The physical ACKlevel pointer is advanced in the physical queue based on the relative position of corresponding logical ACKlevel pointers maintained by the logical queues.

Abstract: A broker may be used as an intermediary to exchange messages between producers and consumers. The broker may store and dispatch messages from a physical queue stored in a persistent memory. More specifically, the broker may enqueue messages to the physical queue that are received from producers and may dispatch messages from the physical queue to interested consumers. The broker may further utilize one or more logical queues stored in transient memory to track the status of the messages stored in persistent memory. As messages are dispatched to and acknowledged by interested consumers, the broker deletes acknowledged messages from the physical queue. The messages deleted are those preceding a physical ACKlevel pointer that specifies the first non-acknowledged message in the physical queue. The physical ACKlevel pointer is advanced in the physical queue based on the relative position of corresponding logical ACKlevel pointers maintained by the logical queues.

Abstract: A broker may be used as an intermediary to exchange messages between producers and consumers. The broker may store and dispatch messages from a physical queue stored in a persistent memory. More specifically, the broker may enqueue messages to the physical queue that are received from producers and may dispatch messages from the physical queue to interested consumers. The broker may further utilize one or more logical queues stored in transient memory to track the status of the messages stored in persistent memory. As messages are dispatched to and acknowledged by interested consumers, the broker deletes acknowledged messages from the physical queue. The messages deleted are those preceding a physical ACKlevel pointer that specifies the first non-acknowledged message in the physical queue. The physical ACKlevel pointer is advanced in the physical queue based on the relative position of corresponding logical ACKlevel pointers maintained by the logical queues.