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

Where we started: Internal MS (1999) • 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

Today’s Market: New Slates

Motion Computing LE 1600 LS 800 Sahara i213 12.1”, 1.6GHz Centrino NEC VersaPro, 10.4”, 1.1 GHz Tatung TTAB 10.4”, 1 GHz ULV Fujitsu 5000 10.4/12.1, Indoor/Outdoor 1.1 GHz ULV Tatung B12D 12.1” 1.2 GHz Centrino

C1xx C300 Acer

Today’s Market: New Convertibles

Toshiba M200, 12.1” SXGA+ Gateway M275 14.1”, DVD 1.8 GHz Pentium-M 2 GHz Pentium-M Fujitsu T4000 Averatec C3500 AMD 2200+ 12.1”,

DVD

Electrovaya 1.4 GHz Centrino 12.1”, Biometrics C250 Scribbler SC-2200 SHARP Actius TN10W 12.1”, 1.1 GHz IBM ThinkPad x41 HP tc4200 ViewSonic 12.1”, 1 GHz

Today’s Market: New Hybrids & Ruggeds Hybrid Ruggedized HP Compaq TC1100ULV Celeron or Pentium 10.4”, 1.1 GHz Itronix 8.4”, 933 MHz ULV Walkabout Hammerhead 10.4”, 4.5 lbs 933 MHz P-III M Xplore iX104 10.4” 1.1 GHz ULV

Concept Design: New hinge

A Concept Tablet for Kids

• Low power – (7W) • 8.4” display • Tethered pen • Rugged

OQO Model 1

Other Form Factors

Vulcan FlipStart

Today’s Market: Forecasts • Mobile Market Projections (IDC)

2004 Market share

Ultra-Mobile 0 to 1 spindle, 5-8” screen, < 2 lbs. Consumers, Mobile Professionals CY08 Market: 2.5M, CAGR (04-08): 40% 0%

2006 Market share

1% Ultra-Portable 1 or 2 spindle,10-12” screen, 2-4 lbs.

Mobile Professionals, Information Workers 8% CY08 Market: 28.4M, CAGR (04-08): 51.4%, Thin & Light 2 spindle, 14-15” screen, 4-7 lbs.

Information Workers, Consumers CY08 Market: 51M, CAGR (04-08): 22% 63% Transportable 2 & 3 spindle, 14-17” screen, 7-12 lbs.

Information Workers, Consumers CY08 Market: 8.9M, CAGR (04-08): -11% 30% 17% 63% 19%

2008 Market share

3% 31% 56% 10%

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) * 1.58

t1-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 ≈ CV 2 f (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

a computer system designer.

for

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 CPU clock rate Alto, 1972 6 MHz Memory size 128 KB Memory access time 850 ns Display pixels 606 x 808 x 1 Network Disk capacity 3 Mb Ethernet 2.5/5 MB MS Tablet 2002 600 MHz 256 MB 100 ns 768 x 1024 x 16 100 Mb Ethernet 6 GB Factor 100 2000 8.5

1.5 (x16) 30 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.