Path2SL: Leveraging InfiniBand Resources to Reduce Head-of-Line Blocking in Fat Trees

The number of endnodes in high-performance computing and datacenter systems is constantly increasing. Hence, it is crucial to minimize the impact of network congestion to guarantee a suitable network performance. InfiniBand is a prominent interconnect technology that allows implementing efficient topologies and routing algorithms, as well as queuing schemes that reduce the head-of-line (HoL) blocking effect derived from congestion situations. Here, we explain and evaluate thoroughly a queuing scheme called Path2SL that optimizes the use of the InfiniBand Virtual Lanes to reduce the HoL blocking in fat-tree network topologies.