NOCS-2009 Chita R. Das National Science Foundation/ Pennsylvania State University

Domain Q. NoCs in MPSoC vs. NoCs in CMPs - Are they really different? - At a functional level NOT, but - Typically CMPs are homogenous and SoC’s are heterogeneous -However, with heterogeneous CMPs, many design issues will be common -Future CPU’s would have accelerators, GPU’s, memory (through 3D stacking), etc making them not much different from SoC’s Image Source: IBM Cell and Internet

Workloads Q. Aren't we may be over-hype the importance of NoCs? - Probably YES unless we understand the workload dynamics and show how it can stress the network - Current workloads have low injection rates - Multimedia application (gaming and video) and emerging workloads ( RMS, PARSEC) may stress on-chip networks -Data-Center On Chip -If bandwidth is not stressed then can we virtualize CMP? Image Source: Internet

Programming model Q. NoC universal replacement? - Good to be imaginative!!! -NoC is a substrate for the CMPs/SoCs. It will be great if it influences the programming model -Programming model for multi-cores is a challenge -Compilers/OS may be interconnect aware to enable run-time optimizations -Miracles occur! Image Source: Internet

Next big thing Q. What are the most urgent research issues we should address? - Workload characterization - Power-aware NoCs. - Scalable, adaptable, intelligent, and reusable NoCs for large systems - Adapting emerging technologies like RF, Optical interconnect, 3D, CNT, etc - Application Specific NoC Design - Performance Isolation, QoS, and Fairness - Fault-tolerance - Performance, power, Reliability trade-offs - Understanding the architectural and technology trade-offs Image Source: IBM and Internet

Scope and impact Q. What kind of results should sponsors (e.g., NSF, GRC, companies) expect over the next 5-10 years? “Science” of designing on-chip networks for next generations CMPs/SoCs Original image: