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Title: Improving Valiant Routing for Slim Fly Networks
Valiant routing, the use of a random intermediate node to distribute network traffic, has been proposed for a number of recent HPC network topologies. It is also commonly used as a bulding block for adaptive routing algorithms, which use shortest path routes when possible, but revert to Valiant routing when necessary to avoid hot spots. We show that the version of Valiant routing proposed for the Slim fly topology can cause messages to follow loops, using an edge in both directions before returning to edges of the original shortest path. Removing these loops in the UGAL-L adaptive routing algorithm is shown to provide slight improvements in average latency and also allow the network to carry up to 12% more traffic before saturation.  more » « less
Award ID(s):
1423413
PAR ID:
10047245
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
2017 46th International Conference on Parallel Processing Workshops (ICPPW)
Page Range / eLocation ID:
155 to 161
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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