method a solution for MSP can be found within the same time bound. The problem of finding all pairs of shortest paths in a directed graph with nonnegative edge weights can be solved in O(log 2 n) time using n 3 /log n processors on a CREW PRAM [7]. Therefore, SSP can be solved within the same resou
Termination Detection for Parallel Shortest Path Algorithms
β Scribed by Michelle R Hribar; Valerie E Taylor; David E Boyce
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 322 KB
- Volume
- 55
- Category
- Article
- ISSN
- 0743-7315
No coin nor oath required. For personal study only.
β¦ Synopsis
Shortest path computation is required by a large number of applications such as VLSI, transportation, and communication networks. These applications, which are often very complex and have sparse networks, generally use parallel labeling shortest path algorithms. Such algorithms, when implemented on a distributed memory machine, require termination detection methods; these methods consist of some type of synchronization among all processors. Because global synchronization can be costly, it is assumed that the best termination detection methods synchronize as infrequently as possible. The frequency, however, can significantly impact the idle time of parallel labeling shortest path algorithms. In this paper we analyze the impact of this frequency on the performance, in particular the idle time, and identify when low versus high frequency detection is best. The analysis and results indicate that when the size of the subnetwork assigned to processor is small enough so that the computation time is less than or equal to the communication time within an iteration, high frequency termination detection methods should be used. Otherwise, low frequency methods should be used.
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