NEW TRENDS IN COMPUTER ARCHITECTURE DESIGN

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NEW TRENDS IN COMPUTER ARCHITECTURE DESIGN
Saeid Nooshabadi Arthur Sale University of
Tasmania
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Outline

• Desktop/Server Microprocessor State of the Art
• Current Processors Limit
• Embedded Processors Market
• Mobile Multimedia Computing as New Direction
• Conclusion

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Computer in the NewsTechnology Marches on (1)

• SANTA CLARA, Calif., March 8, 2000 --
• Intel Corporation today introduced the Intel
  Pentium III processor 1.0 GHz (GigaHertz or
  1,000 MegaHertz), the world's highest performance
  microprocessor for PCs. The Pentium III processor
  at 1 GHz delivers a 15 percent performance gain
  over the fastest processors on the market today.
• Source http//www.intel.com

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Computer in the NewsTechnology Marches on (2)

• INTEL DEVELOPER FORUM, Calif., Feb. 15, 2000 -
• Intel Corporation Chairman Andrew S. Grove
  today kicked off the semi-annual Intel Developer
  Forum by demonstrating the company's fastest
  microprocessor a chip running at 1.5 GHz, or 1.5
  billion clock cycles per second, at room
  temperature. Based on a new microarchitecture
  from Intel, the chip is code-named "Willamette."
  (To be marketed towards end of the year)
  Source http//www.intel.com
• Who needs 1.5 GHz Processor?

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State of the Art Alpha 21264

• 15M transistors
• 2 x 64KB caches on chip 16MB L2 cache off chip
• Clock lt1.7 nsec, or gt600 MHz (Fastest Cray
  Supercomputer T90 2.2 nsec)
• 90 watts
• Superscalar fetch up to 6 instructions/clock
  cycle, retires up to 4 instruction/clock cycle
• Execution out-of-order

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Processor Limit DRAM Gap
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Processor-Memory Performance Gap Tax (1)

• Processor Area Transistors
• (cost) (power)
• Alpha 21164 37 77
• StrongArm SA110 61 94
• Pentium Pro 64 88
• 2 dies per package Proc/I/D L2
• Caches have no inherent value, only try to close
  performance gap
• COST F(Area4)

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Processor-Memory Performance Gap Tax (2)

• Microprocessor-DRAM performance gap
• time of a full cache miss in instructions
  executed
• 1st Alpha (7000) 340 ns/5.0 ns  68 clks x 2
  or 136
• 2nd Alpha (8400) 266 ns/3.3 ns  80 clks x 4 or
  320
• 3rd Alpha (21264) 180 ns/1.7 ns 108 clks x 6 or
  648
• 1/2X latency x 3X clock rate x 3X Instr/clock ?
  5X

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Todays Situation Microprocessor

• MIPS MPUs R5000 R10000 10k/5k
• Clock Rate 200 MHz 195 MHz 1.0x
• On-Chip Caches 32K/32K 32K/32K 1.0x
• Instructions/Cycle 1( FP) 4 4.0x
• Pipe stages 5 5-7 1.2x
• Model In-order Out-of-order ---
• Die Size (mm2) 84 298 3.5x
• without cache, TLB 32 205 6.3x
• Development (man yr.) 60 300 5.0x
• SPECint_base95 5.7 8.8 1.6x

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Processors Evaluation Metrics

• SPECint95 Suit of Integer Programs
• SPECft95 Suit of Floating Point Programs
• TCP-C On Line Transaction Processing Programs
  (OLTP)
• All state of the arts processors perform well for
  SPECint95 and SPECft95 (scientific and technical
  applications)
• TCP-C ?

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Processor Limits for TPC-C

• 
  SPEC-
• Pentium Pro
  int95 TPC-C
• Multilevel Caches Miss rate 1MB L2 cache 0.5
  5
• Superscalar (2-3 instr. retired/clock) clks
  40 10
• Out-of-Order Execution speedup
  2.0X 1.4X
• Clocks per Instruction
  0.8 3.4
• Peak performance
  40 10

source Bhandarkar, D. Ding, J. Performance
characterization of the Pentium Pro processor.
Proc. 3rd Int'l. Symp. on High-Performance
Computer Architecture, Feb 1997. p. 288-97.
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Embedded Processor Market

• Over 97 of the processors fabricated
• 50 of the revenues from processor sales
• Embedded devices cover wide range products
• simple devices such as thermostats and toasters
• complex and mission-critical applications such as
  avionics systems.
• In between are phones, facsimile machines, ATM
  switches, digital cameras, automotive
  applications, set-top boxes, ...

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Embedded Processor Design

• Drives the technology Post-PC era
• Embedded processors incorporate capabilities
  traditionally associated with the conventional
  CPUs.
• They are subject to challenging
• cost,
• power consumption,
• and application- imposed constraints.

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Intel Embedded Mobile Celeron Processor

• Available at 600, 566, 533, 500 and 466 MHz.
• Dynamic Execution technology.
• Includes Intel MMX media enhancement technology.
  
• Intel Streaming SIMD Extensions (available on the
  Intel Celeron Processor at 566 and 600 MHz).
• 32 Kbyte (16 Kbyte/16 Kbyte) Level 1 cache.
• 128 Kbyte integrated Level 2 cache.
• 66 MHz Intel P6 micro-architecture's
  multitransaction system bus.
• Intel Chipset support Intel 810 chipset, Intel
  810E chipset, Intel 440BX, Intel 440EX and the
  Intel 440ZX-66 AGPset.
• Power 17 - 30 Watts Source http//www.intel.com

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Desktop/Server Processors Summary (1)

• SPEC performance doubling / 18 months
• Growing CPU-DRAM performance gap tax
• Running out of ideas, competition? Back to 2X /
  2.3 yrs?
• Benchmarks SPEC-int, SPEC-ft, TPC (for OLTP)
• Benchmark highest optimization, ship lowest
  optimization?
• Processor tricks not as useful for transactions?
• Clock rate increase compensated by CPI increase?
• When gt 100 MIPS on TPC-C?

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Desktop/Server Processors Summary (2)

• Embedded processors promising
• Strong ARM 110 233 MHz, 268 MIPS, 0.36W typ.,
  49
• 1/10 cost, 1/100 power, 1/2 integer performance?
• Consolidation of desktop industry? Innovation?
• Time to look for the computing trends and
  applications of tomorrow?

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Billion Transistor Architectures and Stationary
Computer Metrics

• SS Trace SMT CMP IA-64 RAW
• SPEC Int
• SPEC FP
• TPC (DataBse)
• SW Effort
• Design Scal.
• Physical Design Complexity
• (See IEEE Computer (9/97), Special Issue on
  Billion Transistor Microprocessors)
• Very Long Instruction Word (Intel,HP
  IA-64/Merced)
• multiple ops/ instruction, compiler controls
  parallelism
• Coined as the next generation Intel/HP processor
• Renamed Itanium (October 99)

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Current Computer Design with the Bias for the Past

• Most Billion Transistor Architectures show high
  physical design complexity
• Most show impressive performance for SPEC suits
  of programs
• Suitablity
• suitable for high end traditonal applications
• unsuitable for pervasive computing environment of
  the future
• high power budget (gt180 Watts),
• expensive (gt500)
• Applications of past to design computers of future

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Challenge for Future Microprocessors

• ...wires are not keeping pace with scaling of
  other features. In fact, for CMOS processes
  below 0.25 micron ... an unacceptably small
  percentage of the die will be reachable during a
  single clock cycle.
• Architectures that require long-distance, rapid
  interaction will not scale well ...
• Will Physical Scalability Sabotage Performance
  Gains? Matzke, IEEE Computer (9/97)

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Computer in the NewsExpert Talking

• Intel specializes in designing
  microprocessors for the desktop PC, which in five
  years may no longer be the most important type of
  computer. Its successor may be a personal mobile
  computer that integrates the portable computer
  with a cellular phone, digital camera, and video
  game player Such devices require low- cost,
  energy- efficient microprocessors, and Intel is
  far from a leader in that area.
• -David Patterson, NY Times, June 9, 1998
• David Patterson led the design of Berkeley
  RISC Machine, the first RISC computer. He is also
  the author/co-author of two of most popular
  Textbooks on Computer Architecture.

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Post PC Motivation

• Next generation fixes problems of last gen.
• 1960s batch processing slow turnaround ?
  Timesharing
• 15-20 years of performance improvement, cost
  reduction (minicomputers, semiconductor memory)
• 1980s Time sharing inconsistent response
  times ? Workstations/Personal Computers
• 15-20 years of performance improvement, cost
  reduction (microprocessors, DRAM memory, disk)
• 2000s PCs difficulty of use/high cost of
  ownership ? ???

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Computing Trends Post-PC Era

• Multimedia Applications
• real time data types video, speech, animation,
  music
• 90 of desktop cycles will be spent on media
  applications by end of 2000.
• Multimedia workloads will continue in importance
• Image, handwriting, and speech recognition will
  pose other major challenges.
• Pervasive Mobile Computing Devices
• support an expanding range of functions
• challenge is in converging them into a single
  device
• keeping the size, weight, and power consumption
  constant.

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Sony Playstation 2000

• Emotion Engine 6.2 GFLOPS, 75 million polygons
  per second (Microprocessor Report, 135)
• Superscalar MIPS core vector coprocessor
  graphics/DRAM
• Claim Toy Story realism brought to games!

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Intelligent PDA ( 2005?)

• Pilot PDA
• gameboy, cell phone, radio, timer, camera, TV
  remote, am/fm radio, garage door opener, ...
• Wireless data (WWW)
• Speech, vision recog.
• Voice output for conversations

-Speech control of all devices - Vision to see,
- Scan documents, - read bar code, ... -
Measure room
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Billion Transistor Architectures and Mobile
Multimedia Metrics

• SS Trace SMT CMP IA-64 RAW
• Design Scal.
• Energy/power
• Code Size
• Real-time
• Cont. Data
• Memory BW
• Fine-grain Par.
• Coarse-gr.Par.
• Direction for Computer Architecture Research,
  Kozyrakis, Patterson IEEE Computer (11/98)

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New Architecture Directions

• media processing will become the dominant force
  in computer arch. microprocessor design.
• ... new media-rich applications... involve
  significant real-time processing of continuous
  media streams, and make heavy use of vectors of
  packed 8-, 16-, and 32-bit integer and Fl. Pt.
• Needs include high memory BW, high network BW,
  continuous media data types, real-time response,
  fine grain parallelism
• How Multimedia Workloads Will Change Processor
  Design, Diefendorff Dubey, IEEE Computer (9/97)

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Some Media-Processing Functions

• Kernel Vector length
• Matrix transpose/multiply (3D Gr.) vertices at
  once
• DCT (video, comm.) image width
• FFT (audio) 256-1024
• Motion estimation (video) image width, i.w./16
• Gamma correction (video) image width
• Haar transform (media mining) image width
• Median filter (image process.) image width

(from http//www.research.ibm.com/people/p/pradeep
/tutor.html)
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Challenges for Mobile Multimedia

• High performance for multimedia functions
• Energy and power efficiency (lt1 Watt)
• Small size (fit in pocket)
• Low design complexity and high degree of
  scalability (costs few tens of )

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A Better Mobile Multimedia MPUs LogicDRAM

• Embedded DRAM processors one possibility
• Faster logic in DRAM process
• DRAM vendors offer faster transistors same
  number metal layers as good logic process?_at_
  20 higher cost per wafer?
• Called Intelligent RAM (IRAM) since most of
  transistors will be DRAM
• Leave for another presentation
• A Case for Intelligent RAMPatterson, Anderson,
  . IEEE Computer (3/97)

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Mobile Multimedia Conclusion

• 10000X cost-performance increase in stationary
  computers, consolidation of industrygt time for
  architecture/OS/compiler researchers declare
  victory, search for new horizons?
• Mobile Multimedia offer many new challenges
  energy efficiency, size, real time performance,
  ...
• Apps/metrics of future to design computer of
  future!
• Suppose PDA replaces desktop as primary computer?
• Work on FPPP on PC vs. Speech on PDA?

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From the Horse Mouth

• Personal mobile computing offers a vision of the
  future with a much richer and more exciting set
  of architecture research challenges than
  extrapolations of the current desktop
  architectures and benchmarks.
• Put another way, which problem would you rather
  work on improving performance of PCs running
  FPPPPa 1982 Fortran benchmark used in
  SPECfp95or making speech input practical for
  PDAs?
• Direction for Computer Architecture Research,
  Kozyrakis, Patterson IEEE Computer (11/98)

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References

• IEEE Computers Sept. 97, Jan. 98, Aug. 98, Nov.
  98,
• IEEE Micro Dec. 96, Mar. 97, Sept. 97

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Acknowledgement

• Thanks to Dr. Vishv Malhotra for lending me some
  of his IEEE Computer issues.
• Thanks to Prof. Sale for going through the slides
  and making useful suggestions.
• WAIT FOR THE NEXT TWO SLIDES

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Purpose of This Talk

• To get Staff and Students excited about the new
  opportunities for research.
• What would you be doing as a graduate?
• Service Windows NT, and if lucky perhaps UNIX?
• Develop web pages?
• Do more of the same?
• Or rather do something really exciting?
• We need you if you choose the LATTER!
• 50 Post Graduate Scholarship for IT up for grab

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Our Vision and Aim

• Achieve Critical Mass in Research
• Create a Group of Staff Students Working on the
  Problems of Future.
• Pulling Australian IT Research Community Together
• Identifying Niches Where We Can Make
  International Contribution.