Modeling and Simulation for Architecture: Breakout

Arun R.Krste A.

Dave M. Doe H.Y.Derek C.

Lizy J.Kevin L.Dean K.Karen B.

Shekhar B.

Mike P.Chris C.Jim K. John H.

Sudhakar Y.Luiz C.

Steve R.Wilf P.Jim K.

.

Participants

Moderator and Scribe

Darren K. and Arun R.

High level• Lots of discussion about the SW Issues & Apps• Major concern on interaction & interfaces

– between communities– “common language”

• Good at iterative development– Need good starting points– Need an informed path

• Lots of discussion of HW Design space– Caution over multiple metrics– Know performance well– Weaker on power– don’t know about reliability– Cost very hard, but very important

• “Cultural” Barriers & IP Issues

1. Object of Modeling: What to Model

• Goal: “Make Design Decisions”– Gain Insight– “Common Language” “Shared Testbed”

• Need to Support Co-design Loop– Arch. want Application models– Apps. want Architecture models

• Abstraction is needed to deal with Complexity• Different goals for different times/audiences

– Design exploration in terms of power, performance, reliability, and cost– Design validation– SW development

• Lots of parameters in the design space

2. Can we do it now

• Good at iterative refinement• Lots of discussion on need for abstract model w/ parameters

& trend lines (abstract machine model)– Iteratively approaches– Iterative series of definitions (multiple scopes, levels of

abstraction)– Good at evolutionary approaches– captures key parameters– capture disruptive changes– Correct abstractions are CRITICAL

• Caution: radical changes make things difficult, uncertain– Hard to jump 10+ years out

3. Gaps• Some research gaps, some interactional gaps

• “Cultural Barriers”– IP: what is precompetitive? what can we share?– App. vs. HW vs. compiler vs. OS etc...

• Skeleton Applications & Skeleton Architectures– Multiple levels– Correct abstractions– Not assume a single execution model

• Need way to interact between HW & SW• Fidelity vs. Time vs. Scale tradeoffs (decomposability)• Methodology

– What scale? what abstractions? – Need community consensus of what is needed

• Roadmap of Modeling capabilities

Gaps (cont.)

• Infrastructure– Technology models– Lots of discussion for tech. models for disruptive

technologies and how we trust them• Modeling Testbed– Bring together architecture & application skeletons @

Multiple levels of abstraction w/ Technology Modeling• Resources– Access to state of art machines for simulation– Access to state of art machines for validation

4. Community of Interaction

• Application Teams (Co-Design Centers)– Also, OS, Runtime, Compiler

• Different facets within architecture teams– Memory– Processor– Network– Device-level & High level

• Need lots of cross-cutting interaction

5. Measure for Success

• #1: No Surprises in Deployed Machine• Infrastructure is available, used, and broadly

accepted• Influence is demonstrated– Impact of methodology is demonstrated– We know which gaps we filled