Process-pair resource manager implementation of object bags

Abstract

A shared bag, for collecting objects used in object oriented programming, implemented as a process pair resource manager intended to provide concurrent access to multiple threads. The process-pair implementation includes a concurrent aspect and a serial aspect. Each thread gains concurrent access to the shared bag through a registered transaction. The multiple threads can concurrently access the shared bag by passing messages to the concurrent aspect in order to add objects to, or remove objects from the shared bag. The concurrent aspect adds a description of each message, as well as the result of processing each message, to a transaction record associated with the transaction under which the thread is registered. The identity of each removed object is also recorded by the concurrent aspect in the transaction record. At the conclusion of a transaction, the concurrent aspect passes the transaction record to the serial aspect. The serial aspect then replays the transaction, using the transaction record. The serial aspect uses the object identities included in the transaction record to deterministically choose the order in which objects are removed during a transaction. Once the serial aspect has replayed the entire record, it commits or rolls back the transaction. In the event of process, processor, communication, or system failure, the shared bag is always recoverable to reflect all, and only, committed transactions.