Distributed Time-Dependent Contraction Hierarchies

Server based route planning in road networks is now powerful enough to find quickest paths in a matter of milliseconds, even if detailed information on time-dependent travel times is taken into account. However this requires huge amounts of memory on each query server and hours of preprocessing even for a medium sized country like Germany. This is a problem since global internet companies would like to work with transcontinental networks, detailed models of intersections, and regular repreprocessing that takes the current traffic situation into account. By giving a distributed memory parallelization of the arguably best current technique – time-dependent contraction hierarchies, we remove these bottlenecks. For example, on a medium size network 64 processes accelerate preprocessing by a factor of 28 to 160 seconds, reduce per process memory consumption by a factor of 10.5 and increase query throughput by a factor of 25. Key words: time-dependent shortest paths, distributed computati...

• Type: Conference
• Year: 2010
• Where: WEA
• Authors: Tim Kieritz, Dennis Luxen, Peter Sanders, Christian Vetter
• Keywords: Algorithms, Time-dependent Contraction Hierarchies, Time-dependent Shortest Paths, Time-dependent Travel Times, WEA 2010