Final Report Outline

(Draft in Progress)

Four Pieces:

1. Executive Summary
2. Research Solicitation
3. Program Vision (main description)
4. Appendicies

Executive Summary

Target: 2p (starting point might be vision document from June)

• (Congressional Slogan?)
• scaling good, computers everywhere...critical to our lives and economy at many levels
• challenges ahead due to reliability and power
• hints there is something we can do
• need research to develop new solutions
• here's what we think we can do for you
• need leadership (government leadership)

Research Solicitation

Target: 2p

• outline key challenge ahead
• kind of research solicited
• program structure (? program coverage of promising directions?)
• evaluation criteria

Program Vision

• What are you trying to do?
  • Allow continued scaling benefits
    • Reduce energy/operation
    • Reduce $$/gate
    • Increase ops/time with limited power-density budget
  • While maintaining or improving safety
  • Navigate inflection points in Energy and reliability
• Why now?
  • inflection points in reliability, energy
  • critical deployment of computation
  • system size?
• How is it done today?
  • Demand reliable, consistent device operation
    • Margin for worst-case device effect Of billions, over multi-year lifetime
    • Discard components when devices fail
  • System-level redundancy
  • The niches where above is not good enough are small but important (avionics, medical)
    • Spend considerable $$, energy for reliability
    • E.g. Brute-force replication
    • Many-year performance lag behind commercial systems
• Trends?
  • power limited trends? ... gap from margining?
  • voltage scaling (ITRS)

  • decreased dopants --> variability (ITRS)

  • roadmap work on rate of variation-induced defects
  • increasing transistors/chip
  • increasing system system sizes (supercomp, data centers)
  • decreased opportunity for burnin
  • increase wearout effects

  • decreased critical charge --> increased upset susceptibility

  • roadmap work on {intrinsic,extrinsic} upsets?
  • GDP in electronics?
  • electronics in critical systems
• What can we accomplish?
  • Build reliable systems from unreliable components Efficiently compensate for unpredictable devices through cooperation at higher levels of system stack
  • ground goals
    • scale how much further?
    • allow how many more ops/Joule?
    • how close to raw scaling?
    • extend component life by how much?
    • ...more... (depend on / synch with challenges)
• What's new? (Ideas and promising directions)
  • Ubiquitously/pervasively exploit:
    • Cross-layer codesign --- Multi-level tradeoffs (generalization of hardware/software)
      • (incl. tools to support, system abstractions, algorithm design)
    • Design prepared for self-assessment of safety margins and repair
    • Cooperative filtering of errors at multiple levels
    • Strategic, low-overhead redundancy
    • Differential reliability
    • Scalable and adaptive solutions
• Why do this?
  • reliability matters for everything moving forward...just a matter of how much
  • Allow scaling to continue without sacrificing safety
    • Continued reduction in energy/op
    • Continued reduction in $$/op
    • Maintain or extend component lifetimes
    • How much further?
  • Allow construction of larger, dependable systems
  • Make infrastructural technology worthy of the trust we place in it
  • Specific big wins (challenges overcome) from focus groups?
    • feasible to fly commercial? and/or have any access to most advanced technology? (close commercial/aerospace component gap?); allow areospace to exploit modern electronics?
    • advanced tech safe for drive-by-wire?
    • enable larger (more components, computation) medical devices?
    • enable supercomputers able to solve XXX problems?
    • ??? review focus group output and select appropriate to highlight here ???
  • Can't have security w/out getting resilience under control ?
  • Why government leadership?
• Big Science Questions?
  • How do we organize, manage, and analyze layering for cooperative fault mitigation?
  • How do we best accommodate repair?
  • What is the right level of filtering at each level of the hierarchy?
  • Can we establish a useful theory and collection of design patterns for lightweight checking?
  • What would a theory and framework for expressing and reasoning about differential reliability look like?
  • Can a scalable theory and architectures that will allow adaptation to various upset rates and system reliability targets be developed?
• Critical Questions? (big risk items? ... more strategic questions?)
  • enable concurrent research in understanding low-level upset, fatigue effects with ever changing technology along with high-level mitigation
  • manage developer burden (avoid increasing)
  • pushing more complexity into software, when haven't mastered reliable software
  • ??? others
• Metrics, Goals, Measure and manage programs
  • Goals of metrics
    • assess if proposed research proposing to attack the right problems?
    • measure if research making progress on solving the problem?
  • Some possible, primary metrics
    • Energy/Op at noise rate and performance target (Noise rate: defects, variation wear, transients)
    • Post-fab adaptability to range of noise rates
    • Timeliness and quality of adaptation
  • Recommendations from metrics group
• Examples and Illustrative Scenarios
  • Processor
  • SoC
  • High-level software
• Challenge problems and areas of pain
  • common/cross-cutting challenges
  • by focus group (5)
• Mission Impacts? (perhaps related to stuff trying to summarize above under specific challenges overcome---but, the detail support goes here; this is also the challenges/targets/opportunties for more mission oriented agencies)
  • security
  • cyberphysical
  • satellite
  • supercomputer
  • ???
• Infrastructure
• Layer discussion and community contributions: probably good to have a clear description of the layers and callout the wide range of communities that could participate in this research
• Process and Participants
  • summarize activities of group (meetings, wiki, focus groups...)
  • comprehensive list of participants

Appendix

• focus group reports