Pushing the Limits of Irregular Access Patterns on Emerging Network Architecture: A Case Study

Irregular applications pose considerable challenges to modern computer systems, especially in distributed environments, where traditional high-performance networks are optimized for large message transfers. In this work, we analyze performance of an irregular application proxy benchmark running over traditional MPI/Infiniband as well as over the Data Vortex network, an emerging network architecture optimized for small packets. Our goal is to identify the challenges posed by irregular applications and explore how emerging highperformance communication networks can cope with some of them. In particular, we analyze the performance of the Data Vortex interconnection network using the HPCC RandomAccess benchmark with different look-ahead buffer sizing to simulate varying degrees of irregularity. We use multiple implementations of the HPCC RandomAccess benchmark for both MPI/Infiniband and Data Vortex networks, with various degrees of optimizations. We compare Data Vortex results to a traditional high-bandwidth Infiniband network at scale and show that Data Vortex networks provide linear scalability and high performance.