Dynamic Connectivity in Constant Parallel Rounds

Series: 
ACO Student Seminar
Friday, September 14, 2018 - 1:05pm
1 hour (actually 50 minutes)
Location: 
Skiles 005
,  
CS, Georgia Tech
,  
Organizer: 
 We study the dynamic graph connectivity problem in the massively parallel computation model. We give a data structure for maintaining a dynamic undirected graph that handles batches of updates and connectivity queries in constant rounds, as long as the queries fit on a single machine. This assumption corresponds to the gradual buildup of databases over time from sources such as log files and user interactions. Our techniques combine a distributed data structure for Euler Tour (ET) trees, a structural theorem about rapidly contracting graphs via sampling n^{\epsilon} random neighbors, as well as modifications to sketching based dynamic connectivity data structures. Joint work with David Durfee, Janardhan Kulkarni, Richard Peng and Xiaorui Sun.