The Tablet PC at Five

Chuck Thacker

Distinguished Engineer

Microsoft Corporation

July 20, 2005

Talk outline

• Tablet history• The Tablet today• Tablet futures• Limits on computers

– What Moore actually said.– Implications for computers.– Other limits

• What about software?• Conclusions

Prehistory – before 2000

• Lots of earlier attempts – mostly failures.– DEC, Go, Newton, Pen Windows

• Technology wasn’t ready

• But vertical markets had limited success.

• Needed: better UI, better handwriting recognition (without relying on it).

• Key: Better digitizer (with hover).

An earlier attempt -- 1983

• TRS 80 Model 100• Reporters and students

loved it• Ran for days on AA cells• Solved most computing

needs for its (low aspiration) users.

Another attempt -- 1993

• DEC Lectrice• 5.5 pounds• 1.5 hour battery• Wireless network• $5K LCD panel• VxWorks OS, X11 server

optimized for reading

• Microsoft proof of concept– Transmeta TM5800– 256MB DRAM, 20GB HDD– 10.4” Slate

• Good points:– Proved viability– Pushed the Power Efficiency Envelope

• 5 Hours runtime, 200 Hours standby– Provided a development platform

to get MS to Tablet PC launch.• On the Other Hand:

– It was so sloooooow

Where we started: Internal MS (1999)

Today’s Market: New Slates

Sahara i213

12.1”, 1.6GHz Centrino

Motion

Computing

Tatung TTAB

10.4”, 1 GHz ULV

Tatung B12D

12.1” 1.2 GHz Centrino

Fujitsu 5000

10.4/12.1, Indoor/Outdoor

1.1 GHz ULV

NECVersaPro, 10.4”, 1.1 GHz

LE 1600

LS 800

Today’s Market: New Convertibles

Acer

C1xx

C300

C250

Averatec C3500AMD 2200+

12.1”, DVD

Electrovaya1.4 GHz Centrino

12.1”, Biometrics

Scribbler SC-2200

Gateway M275

14.1”, DVD

1.8 GHz Pentium-M

SHARPActius TN10W12.1”, 1.1 GHz

ToshibaM200, 12.1” SXGA+

2 GHz Pentium-M

ViewSonic

12.1”, 1 GHz

Fujitsu

T4000

IBM ThinkPad x41

HP tc4200

Today’s Market: New Hybrids & Ruggeds

HP Compaq TC1100ULV Celeron or Pentium

10.4”, 1.1 GHz

Walkabout Hammerhead

10.4”, 4.5 lbs

933 MHz P-III M

Hybrid Ruggedized

Itronix8.4”, 933 MHz ULV

Xplore iX10410.4” 1.1 GHz ULV

Concept Design: New hinge

A Concept Tablet for Kids

• Low power– (7W)

• 8.4” display

• Tethered pen

• Rugged

Other Form Factors

Vulcan FlipStartOQO Model 1

Today’s Market: Forecasts

• Mobile Market Projections (IDC)

Ultra-Portable1 or 2 spindle,10-12” screen, 2-4 lbs.

Ultra-Mobile0 to 1 spindle, 5-8” screen, < 2 0 to 1 spindle, 5-8” screen, < 2

lbs. lbs.

Thin & Light2 spindle, 14-15” screen, 4-7 lbs.2 spindle, 14-15” screen, 4-7 lbs.

Transportable2 & 3 spindle, 14-17” screen, 7-12 lbs.2 & 3 spindle, 14-17” screen, 7-12 lbs.

0%0%

8%8%

30%30%

2004Market share

63%63%

1%1%

17%17%

19%19%

2006Market share

63%63%

3%3%

31%31%

10%10%

2008Market share

56%56%

Consumers, Mobile ProfessionalsCY08 Market: 2.5M, CAGR (04-08): 40%

Mobile Professionals,Information WorkersCY08 Market: 28.4M, CAGR (04-08): 51.4%,

Information Workers,Consumers CY08 Market: 51M, CAGR (04-08): 22%

Information Workers,ConsumersCY08 Market: 8.9M, CAGR (04-08): -11%

Moore’s Law (1967)

• Not really a “law”, but an observation, intended to hold for “..the next few years”.

• (Nt/A)(t1) = (Nt/A)(t0) * 1.58t1-t0 (t in years)

• Most exponential curves in the real world turn out to be “S” shaped, but Moore’s observation has held for 35 years.

The Woolly Bear Book of VLSI scaling

• Scaling requires lithography and process changes.• Get more and faster transistors in the same area.• Power per transistor goes down, power per unit area

goes up (sometimes way up).• Power ≈ CV2f (plus leakage)

How to use Moore’s Law

• Lower cost: Same Nt, reduced A (“die shrinks”) used in video consoles.

• More complex chips: Larger Nt, same A.– Lower the voltage and increase frequency– Add larger caches to overcome latency– Add architectural features to increase ILP

• Superchips (SOC): Increase Nt and A.

Moore’s Law for Memory

• Capacity improvement: 1,000,000 X since 1970.

• Bandwidth improvement: 100 X.

• Latency reduction: only 10-20 X.– Dealing with latency is the largest problem for

a computer system designer.

Moore’s Law for Processors

• More complex designs

• More than one processor on a chip (homogeneous).

• More than one processor, with specialized functions, e.g. graphics– Graphics performance is improving much

faster than CPU performance.

Thirty years of progress

Item Alto,

1972

MS Tablet

2002

Factor

CPU clock rate 6 MHz 600 MHz 100

Memory size 128 KB 256 MB 2000

Memory access time

850 ns 100 ns 8.5

Display pixels 606 x 808 x 1 768 x 1024 x 16 1.5 (x16)

Network 3 Mb Ethernet 100 Mb Ethernet 30

Disk capacity 2.5/5 MB 6 GB 2400/1200

Possible Future Limits

• Physical limits:– “Atoms are too large, and light is too slow”– Today, the problem isn’t making the transistors faster, it’s the

time for signals to propagate on the wires (latency again).– Power. Lots of transistors => lots of power. Cooling is hard.

• Design complexity:– Designing a billion-transistor chip takes a large team, even with

good design tools.– The “junk DNA” problem.

• Economics:– Factories are very expensive.

Scaling Limits

• Voltage scaling is about over. It’s very hard to operate below 1 volt.

• Frequency increases are also difficult. – Intel runs out at 3 – 4 GHz.

• Static leakage is also a big problem.

• So, we’ll see more transistors in the future, but they won’t be better or faster transistors.

Future processors

• We’ll see chips with many processor cores.• Each core will be simpler than today’s

superscalar machines. Probably hyperthreaded, to hide latency.

• Optimized to increase thread-level parallelism, rather than instruction-level parallelism.

• The story about caching is very unclear…• See Intel’s “Platform 2015” white papers.

Other Limits

• Not all technologies used in computers follow Moore’s Law– Disks don’t– Displays don’t– Batteries don’t

• The bandwidth vs. latency problem.– See D. Patterson, “Latency Lags Bandwidth”,

CACM, October 2004

What about software?

• For scientific computing and servers, the future seems fine.– There are lots of important problems that are

embarrassingly parallel.

• For client software, the picture is more bleak.

Many-core challenges for clients

• Windows doesn’t use threads well– Exceptions: Kernel, SQL– Competitors don’t do any better

• Applications don’t use threads well– Outlook is the poster child– Until recently, inking on Tablet was problematic

• Problems:– Writing multi-threaded code is hard– Threading model and primitives are overly complicated– Threads don’t compose – Debugging multi-threaded code is harder– Testing multi-threaded code is a crapshoot– Tool support isn’t very good

Possible paths forward

• Better language support for parallelism– Cω, Atomic transactions

• Better tools– Analyze liveness and safety statically– Model checking– Dynamic race detection

• Better libraries

• Better education

Conclusions

• Popularity of portable devices, including Tablet PC, is growing

• Much of the innovation in the industry is in this area.

• Energy-efficiency can open up new markets.

• Silicon trends favor the high end• There are lots of challenges and

opportunities for new software.