The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 17, 2007
Filed:
May. 13, 2003
Boleslaw K. Szymanski, Newtonville, NY (US);
Gang Chen, Troy, NY (US);
Boleslaw K. Szymanski, Newtonville, NY (US);
Gang Chen, Troy, NY (US);
Rensselaer Polytechnic Institute, Troy, NY (US);
Abstract
Lookback is defined as the ability of a logical process to change its past locally (without involving other logical processes). Logical processes with lookback are able to process out-of-timestamp order events, enabling new synchronization protocols for the parallel discrete event simulation. Two of such protocols, LB-GVT (LookBack-Global Virtual Time) and LB-EIT (LookBack-Earliest Input Time), are presented and their performances on the Closed Queuing Network (CQN) simulation are compared with each other. Lookback can be used to reduce the rollback frequency in optimistic simulations. The relation between lookahead and lookback is also discussed in detail. Finally, it is shown that lookback allows conservative simulations to circumvent the speedup limit imposed by the critical path.