1. © 2006 Cisco Systems, Inc. All rights reserved. 1 Cisco Routing Research Seminar August 29, 30 th 2006 System Power Challenges Garry Epps, David Tsiang, Tom Boures Cisco Systems Distinguished Engineers

2. 2 © 2006 Cisco Systems, Inc. All rights reserved. Goals of this session Discuss the system power issue this industry faces over the next 5-10 years Engage experts in both academia and industry Promote awareness

3. 3 © 2006 Cisco Systems, Inc. All rights reserved. Agenda Garry Epps Cisco Distinguished Engineer Cisco Systems Introduction, Cisco perspective on problem statement Professor Mark Horowitz Director of Computer Systems Laboratory Stanford University Scaling, Power and the future of CMOS Shekhar Y. Borkar Intel Fellow, Director, Microprocessor Research Intel Extending and Expanding Moore’s Law – Challenges and Opportunities Ajith Amerasekera TI Fellow, Director of ASIC Technology Strategy Texas Instruments System Power Challenges – an ASIC Viewpoint Evaldo Martins Miranda Power and Thermal Design Manager Analog Devices Power / Thermal Impact of Network Computing Professor Alfonso Ortega James Birle Professor of Energy Technology Villanova University Thermal Engineering Research Motivated by Cooling of Electronic Systems Panel Discussion All

4. 4 © 2006 Cisco Systems, Inc. All rights reserved. System requirements are scaling faster than both silicon and cooling technology Limits being reached: –Total system power –Individual device power –Cooling infrastructure Problem Statement

5. 5 © 2006 Cisco Systems, Inc. All rights reserved. Moore’s law x2/18m DRAM access rate x1.1/18m Silicon speed x1.5/18m Router Capacity x2.9/18m 1 10 100 1000 10000 1993199419951996199719981999 2000 2001 2002200320042005 Growth, Growth, Growth!!!

6. 6 © 2006 Cisco Systems, Inc. All rights reserved. Shortfall! Shortfall is overcome by architectural innovation and trading off: Performance, functionality, programmability, physical size/density  Very hard to sustain long-term Technology is falling behind demand

7. 7 © 2006 Cisco Systems, Inc. All rights reserved. Where is all the power going? Data from an in-flight CRS linecard program, 9 ASICs @ 90nm

8. 8 © 2006 Cisco Systems, Inc. All rights reserved. Where is all the power going? Core Clock Frequency Device Pin Count Die Size Historical ASIC data, Cisco Systems GSR/CRS 1997-2004

9. 9 © 2006 Cisco Systems, Inc. All rights reserved. Industry Heat Density Trends “…Energy efficiency of equipment has not dropped at the same rate as product density…” Data from Thermal Management Consortium (includes Cisco)

10. 10 © 2006 Cisco Systems, Inc. All rights reserved. Datapoint: Cisco Global Power Consumption Labs represent: – 80% of total power, but only 20% of total floorspace – 70% of total cooling capacity (25k “Tons” of cooling) Cisco global power consumption grew ~13% in the last year ~350M kWH  ~400M kWH Utilities are giving strong incentives to implement power-saving measures 1 “Ton” == 12000 BTUHours of cooling

11. 11 © 2006 Cisco Systems, Inc. All rights reserved. Product example Largest Routing System available today is CRS-1 Linecard Chassis: 1.28Tbps, 13.6kW Switch Fabric Chassis: 8kW

12. 12 © 2006 Cisco Systems, Inc. All rights reserved. Product example Maximum configuration: 92Tbps  72 x LC chassis + 8 x Fabric chassis ~1 MegaWatt!!!

13. 13 © 2006 Cisco Systems, Inc. All rights reserved. Specific issues we face - 1 Delivering electrical power to the system: –More 48VDC feeds –Battery capacity –Generator capacity –Cost of power

14. 14 © 2006 Cisco Systems, Inc. All rights reserved. Specific issues we face - 2 Keeping individual chips/hot-spots to a ‘safe’ operating temperature –Reliability/longevity of Silicon –40-50W/per device max. Traditional requirements: –Standardised form-factors –Highly-reliable –Serviceable, slot-based –Air cooled via Fans/Blowers –Front to back air –Continued operation at 50C Airflow

15. 15 © 2006 Cisco Systems, Inc. All rights reserved. Specific issues we face - 3 Removing heat from the box –Huge air blowers/fans –Excessive noise –Physical dimensions of systems –Weight of system Building HVAC systems maxed –Typical Central Office designed for 2kW per rack –Current systems  10-13kW per rack –Future systems  10kW per ½ rack

16. 16 © 2006 Cisco Systems, Inc. All rights reserved. Power Density example Empty racks

17. 17 © 2006 Cisco Systems, Inc. All rights reserved. Potential solution areas 1.Dealing with high system power capacity –Getting the power into the box –Getting the heat out of the chips –Getting the heat out of the box –Getting the heat out of the building 2.Take less power to do the “same” function Whatever approach we take, needs to be cost effective, reliable and manufacturable

18. 18 © 2006 Cisco Systems, Inc. All rights reserved. Potential solution areas - 1 Take less power to do the “same” function Redefine the definition of “same”: –Shift functionality from one place in network to another e.g. move security from core to edge –May compromise network integrity/function –Would not be well accepted by operators –Edge boxes are just as power-hungry today

19. 19 © 2006 Cisco Systems, Inc. All rights reserved. Potential solution areas - 2 Use the same technology more efficiently: –Circuit optimisations (COT) –Reduce the conservatism (overdesign) –Adaptive power supplies –Optimise logic design/architecture/algorithms –Clock tricks –Asynchronous design –Are we overlooking something from the handheld/mobile world? –What else?

20. 20 © 2006 Cisco Systems, Inc. All rights reserved. Potential solution areas - 3 Improve/evolve the underlying (CMOS) technology: –Process improvements, materials changes e.g. Strained silicon, SiGe, SOI, etc… –Reduce the leakage current somehow –Where could this take us, what are the limits?

21. 21 © 2006 Cisco Systems, Inc. All rights reserved. Potential solution areas - 4 Change the underlying system technology: e.g. Move selected functions from electrical to optical domain via Waveguides, Holographics, optical fibers

22. 22 © 2006 Cisco Systems, Inc. All rights reserved. Summary – call to arms System capacity will continue to grow Silicon is not maintaining performance/power ratio Practical air-cooling limits already reached – system and facilities We need to find solutions!

23. 23 © 2006 Cisco Systems, Inc. All rights reserved. Questions?

24. 24 © 2006 Cisco Systems, Inc. All rights reserved. Agenda Garry Epps Cisco Distinguished Engineer Cisco Systems Introduction, Cisco perspective on problem statement Professor Mark Horowitz Director of Computer Systems Laboratory Stanford University Scaling, Power and the future of CMOS Shekhar Y. Borkar Intel Fellow, Director, Microprocessor Research Intel Extending and Expanding Moore’s Law – Challenges and Opportunities Ajith Amerasekera TI Fellow, Director of ASIC Technology Strategy Texas Instruments System Power Challenges – an ASIC Viewpoint Evaldo Martins Miranda Power and Thermal Design Manager Analog Devices Power / Thermal Impact of Network Computing Professor Alfonso Ortega James Birle Professor of Energy Technology Villanova University Thermal Engineering Research Motivated by Cooling of Electronic Systems Panel Discussion All