Object lock management system with improved local lock management and global deadlock detection in a parallel data processing system
Patent 5682537 Issued on October 28, 1997. Estimated Expiration Date: August 31, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
An object lock management system for use in a parallel data processing system where objects are accessible by processing activities on computing nodes within the parallel system. The system includes local lock control elements, where each of the local lock control element coordinates the locking of a predetermined set of objects. In particular, each local lock control element grants locks or queues lock requests in response to lock requests. Lock information is selectively reported to a global deadlock detector which performs deadlock detection. The global deadlock detector instructs the local lock control elements to release selected locks and queued lock requests upon detecting a deadlock. Lock information is reported to the global deadlock detector periodically and only for queued lock requests that have timed-out, whereby message traffic and processing overhead is reduced in the parallel system.
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August 31, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
