Fast barrier synchronization in wormhole k-ary n-cube networks with multidestination worms

This paper presents a new approach to implement fast barrier synchronization in wormhole k-ary n-cubes. The novelty lies in using multidestination messages instead of the traditional single destination messages. Two different multidestination worm types, gather and broadcasting, are introduced to implement the report and wake-up phases of barrier synchronization, respectively. Algorithms for complete and arbitrary set barrier synchronization are presented using these new worms. It is shown that complete barrier synchronization in a k-ary n-cube system with e-cube routing can be implemented with 2n communication start-ups as compared to 2n log₂ k start-ups needed with unicast-based message passing. For arbitrary set barrier, an interesting trend is observed where the synchronization cost keeps on reducing beyond a certain number of participating nodes