Background: Since June 2015, the Office of Advanced Scientific Research (ASCR) has partnered with each of the scientific program offices in the DOE Office of Science (SC) to hold six separate Exascale Requirements Reviews. The reviews served to identify mission critical science objectives that require HPC computing, storage and networking for the 2020-2025 timeframe within each program office and help determine future requirements for a computing ecosystem including data, software, libraries/tools, as well as the full range of computing needs (small cluster to exascale). The reviews were targeted to help ASCR develop a strategic roadmap to inform future computational and data facility investments as well as partnership opportunities between ASCR and SC science programs.

Opportunity to Deepen Benefit to Office of Science: Although a goal of the Exascale Requirements Review process was to inform ASCR's strategic roadmap, the exercises were also seen, and designed, to identify the full range of computational and data needs from partner offices, not just those needs that have traditionally been central to ASCR's mission space. The completion of the six reviews provide a unique opportunity to identify and describe computational rate limiters that are in common across the Office of Science.

To realize the full value of the reviews to SC the ASCR Facilities are holding an Exascale Requirements Crosscut Review. The deliverable from this meeting will include a report written by the ASCR Centers summarizing requirements, findings, and identifying cross-cutting Office of Science computational ecosystem needs.

Currently Planned Meeting Objectives:

• ASCR Centers present a summary of findings for comment and feedback, with a focus on identifying common requirements across the six SC program offices
• Office of Science participants with diverse technical expertise, will discuss common technical challenges and priorities, and opportunities for partnering across the Office of Science

Participation in this review requires formal registration where participants are largely expected to include partner SC office program managers and thought leaders from previous exascale requirements reviews. Space is limited so registration requests that exceed participant limits will be waitlisted in the event that additional space becomes available. This will be a 1 ½ day meeting, March 9-10, 2017, and will be held at the Sheraton Tysons Corner Hotel, Tysons, VA.