As data sets from DOE user science facilities grow in both size and complexity there is an urgent need for new capabilities to transfer, analyze and manage the data underlying scientific discoveries. LBNL's Superfacility project brings together experimental and observational research instruments with computational and network facilities at the National Energy Research Scientific Computing Center (NERSC) and the Energy Sciences Network (ESnet) with the goal of enabling user science.Here, we report on recent innovations in the Superfacility project, including advanced data management, API-based automation, real-time interactive user interfaces, and supported infrastructure for "edge" services.

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As bytes-per-FLOP ratios continue to decline, communication is becoming a bottleneck for performance scaling. This paper describes bandwidth steering in HPC using emerging reconfigurable silicon photonic switches. We demonstrate that placing photonics in the lower layers of a hierarchical topology efficiently changes the connectivity and consequently allows operators to recover from system fragmentation that is otherwise hard to mitigate using common task placement strategies. Bandwidth steering enables efficient utilization of the higher layers of the topology and reduces cost with no performance penalties. In our simulations with a few thousand network endpoints, bandwidth steering reduces static power consumption per unit throughput by 36% and dynamic power consumption by 14% compared to a reference fat tree topology. Such improvements magnify as we taper the bandwidth of the upper network layer. In our hardware testbed, bandwidth steering improves total application execution time by 69%, unaffected by bandwidth tapering.

Abstract-Delay tolerant networks are a type of wireless mobile networks that do not guarantee the existence of a path between a source and a destination at any time. In such a network, one of the critical issues is to reliably deliver data with a low latency. Naive forwarding approaches, such as flooding and its derivatives, make the routing cost (here defined as the number of copies duplicated for a message) very high. Many efforts have been made to reduce the cost while maintaining performance. Recently, an approach called delegation forwarding (DF) caught significant attention in the research community because of its simplicity and good performance. In a network with N nodes, it reduces the cost to O( √ N ) which is better than O(N ) in other methods. In this paper, we extend the DF algorithm by putting forward a new scheme called probability delegation forwarding (PDF) that can further reduce the cost to O(N log 2+2p (1+p) ), p ∈ (0, 1). Simulation results show that PDF can achieve similar delivery ratio, which is the most important metric in DTNs, as the DF scheme at a lower cost if p is not too small. In addition, we propose the threshold probability delegation forwarding (TPDF) scheme to close the latency gap between the DF and PDF schemes.