System Architecture

1
Welcome to the course System
Architecture winter term 2001/2002
2
Organization
Organization History of Systems Analogy to
Architecture Introduction Motivation by
Example Preview
3
Organization

• Lecturer
• Gerd Liefländer
• System Architecture Group
• http//i30www.ira.uka.de
• E-mail lief_at_ira.uka.de
• Phone [phone]
• Meeting Times Tuesday 1130 14.00
• Office 160, 1. Floor, Informatik-Neubau
  (50.34)
• Secretary Andrea Engelhart
• E-mail engelhart_at_ira.uka.de
• Phone [phone]
• Office 159, 1. Floor, Informatik-Neubau
  (50.34)

4
Staff Members

• Gernot Heiser (SAOSP, Hot Systems)
• Kevin Elphinstone (Scheduling, Seminar, HS)
• Volkmar Uhlig (SMP, Teaching Assistant 1, HS)
• Espen Skoglund (Persistence, TA 2, HS)
• Uwe Dannowski (Portability, TA 3, HS)
• James McCuller (System Administrator)
• Heinz Zoller (Web-Master)
• Email familyname_at_ira.uka.de

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http//i30www.ira.uka.de

• Anything is on the Web
• Lectures (slides)
• Exercises
• Solutions
• Documents
• Links to other Web Sides
• Planning a Forum

6
Forum (newsgroup)

• You can ask questions via email
• You can point to weak points on the slides or
• in a questions within one of the assignments
• Each of you may answer to any question
• Ill answer over weekend if still necessary
• Ill close the forum if it will be abused
• Only related topics to system architecture allowed

7
Organization
System Architecture
Lectures
Mo 15.10
Mo 22.10
Mo 29.10
Mo 05.11
Mo 12.11
Mo 19.11
Tu 16.10
Tu 23.10
Tu 30.10
Tu 06.11
Tu 13.11
Tu 20.11
Mo 26.11
Mo 03.12
Mo 10.12
Mo 17.12
Mo 24.12
Mo 31.12.
Christmas Vacancies
Tu 27.11
Tu 04.12
Tu 11.12
Tu 18.12
Tu 25.12
Tu 01.01
Mo 07.01
Mo 14.01
Mo 21.01
Mo 28.01
Mo 04.02
Mo 11.02
Tu 08.01
Tu 15.01
Tu 22.01
Tu 29.01
Tu 05.02
Tu 12.02
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Organization
System Architecture
Hot Systems
Lectures
Mo 15.10
Mo 22.10
Mo 29.10
Mo 05.11
Mo 12.11
Mo 19.11
Tu 16.10
Tu 23.10
Tu 30.10
Tu 06.11
Tu 13.11
Tu 20.11
Mo 26.11
Mo 03.12
Mo 10.12
Mo 17.12
Mo 24.12
Mo 31.12.
Christmas Vacancies
Tu 27.11
Tu 04.12
Tu 11.12
Tu 18.12
Tu 25.12
Tu 01.01
Mo 07.01
Mo 14.01
Mo 21.01
Mo 28.01
Mo 04.02
Mo 11.02
Tu 08.01
Tu 15.01
Tu 22.01
Tu 29.01
Tu 05.02
Tu 12.02
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Organization
starting next week (Oct 24/26)
Tutorials
Group Weekday Time Room Tutor T1 Wednesday
09.45 - 11.15 SR -118 Alexander
Elbs T2 Wednesday 09.45 - 11.15 SR -119
Andreas Haeberlen T3 Wednesday 09.45 - 11.15 SR
-120 Horst Wenske T4 Friday 09.45 -
11.15 SR -118 Christian Ceelen T5 Friday 09.
45 - 11.15 SR -119 Stefan Wagner T6 Friday 0
9.45 - 11.15 SR -120 Christian Schwarz We
offer tutorials every week!
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Organization
Tutorials
you can register yourself electronically to a
tutorial on the System Architecture exercise
page via http//i30www.ira.uka.de/
Group Weekday Time Room
Tutor T1 Wednesday 09.45 - 11.15 SR -118
Alexander Elbs T2 Wednesday 09.45 - 11.15 SR
-119 Andreas Haeberlen T3 Wednesday 09.45 -
11.15 SR -120 Horst Wenske T4 Friday 09.4
5 - 11.15 SR -118 Christian
Ceelen T5 Friday 09.45 - 11.15 SR -119
Stefan Wagner T6 Friday 09.45 - 11.15 SR -120
Christian Schwarz We offer tutorials every
week!
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Organization
Tutors
Group/Name E-mail Phone Room Meeting Time T1
Elbs elbs_at_ira.uka.de 608-8970 161 Tue 1130 -
1300 T2 Haeberlen haeberlen_at_ira.uka.de 608-2645
162 Mon 1400 - 15.30 T3 Wenske wenske_at_ira.uka.
de 608-4055 155 Tue 11.30 - 13.00 T4
Ceelen ceelen_at_ira.uka.de 608-4055 155 Thu 1545 -
1715 T5 Wagner swagner_at_ira.uka.de 608-3836 163 T
hu 1130 - 1300 T6 Schwarz schwarz_at_ira.uka.de 60
8-3837 160 Tue 11.30 - 13.00
12
Organization
Exercises

• 10 x non-programming assignments
• Abstract discussion exercises
• Problem solving exercises
• 2 x programming assignments
• Designing, coding, and testing
• Assignments (and solutions) published at
• http//i30www.ira.uka.de/courses/winter01-02
  /Exer_SysArch/index.html
• Assignment 1 already published.
• Discussed in the tutorials next week.

some weeks later
13
Organization
Why exercises and what do we expect from you?

• Exercises will
• Help you to understand (learning by doing)
• Train you to reason appropriately
• Train you to apply in practice what youve
  learned

You might/should try to solve the exercises
within a team, but you must be able to present
your solutions on your own!
14
Organization

• Examination
• Voluntary midterm training exam to get familiar
  with the requirements in the final exam (1 h)
• Friday 21.12. 2001
• 1. Final exam ??. ??. 2002
• 2. Alternate final exam ST 2002
• General Examimation Rules
• work on your own
• no text book
• no other resources, teaching/learning aids, etc.

15
Organization
Bakkalaureat

• Since 3 years our faculty offers an non-official
  Bachelor title.
• Those participating in this non-official Bachelor
  program
• have to fulfill additional requirements after
  Vordiplom
• 5 Exercise certificates out of the 8 mandatory
  lectures
• or
• 4 Exercise certificates a graded study thesis
  
• 1 practice (Praktikum)
• To get an exercise certificate in the lecture
  SYSTEMARCHITECTURE, you have to
• pass the final examination and
• present results (at least 4 times) in the
  tutorials. (Tutors will randomly select
• bakkalaureat students (and others) for
  presentation.)

• Who needs an exercise certificate in System
  Architecture?
• Please tell your tutor ASAP!

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Organization
Related Courses given by our Group in WT 2001/2002
Hot Systems (course for under- and postgraduate
students, All Espen, Gernot, Kevin, Uwe,
Volkmar, Gerd) Micro-Kernels (study group
Arbeitsgemeinschaft, All) Advanced Systems
(seminar, Kevin, Espen) Linux-Internals
(proseminar, HS 102, Gerd, tutors) System-Archite
cture (base practice, Gerd)
17
Organization
Related Courses given by our Group in ST 2002
Hot Systems (course for undergraduate and
postgraduate students) Unix Internals
(proseminar, Gerd, Volkmar) System Design and
Implementation (course practice, Kevin)
Distributed Systems (course, Gerd) Micro Kernel
Construction (course, Espen, Kevin, Uwe) Real
Time Scheduling (block course, Claude Hamann)
Micro Kernels (study group Arbeitsgemeinschaft
) Advanced Systems II (seminar, Kevin)
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History
System Architecture has been relying on only 45
years of experience. Some milestones (very
incomplete) 1956 IBM 704 OS 1968 THE Dijkstra
(U Eindhoven) 1968 Arpanet Elmer Shapiro,
Crocker, Carr, Rulifson, Stoughton (UCLA,
NWG) 1969 Multics Organick, Saltzer et al.
(MIT) 1970 RC4000 Brinch Hansen (Regnecentralen
Kopenhavn) 1971 Unix Ritchie, Thompson (Bell
Labs) 1978 VM/370 Seawright, MacKinnon
(IBM) 1981 Hydra(OOS) Wulf (MIT) 1986
Amoeba(DS) Mullender (CWI) 1989 Mach
(?K) Rashid (CMU) 1990 WWW Berners-Lee,
Cailliau (Cern) However, we are still looking for
the ideal system fast, robust, secure,
configurable and customizable.
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Analogy
Architects have been relying on more than 30 000
years of experience starting with
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Analogy
Famous Real Architectures, e.g.
Pyramids of Egypt (or Central America) Hanging
Gardens of Babylon Akropolis in Athens Colosseum
in Rome Taj Mahal in India Cathedral Notre Dame
in Paris House of Parliament in London Empire
States Building in New York Giuseppe Meazza in
Milano and many other marvelous architectures
around the globe!
Who knows that?
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Analogy
Good example Hanging Gardens of
Semiramis one of the seven ancient miracles
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Analogy
Bad examples
Tower of Babylon (Sign of Megalomania)
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Analogy
Bad examples
Tower of Babylon (Sign of Megalomania) Cathedral
of Beauvais (Partial Collapse)
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Analogy
Bad examples
Tower of Babylon (Sign for Megalomania) Cathedral
of Beauvais (Partial Collapse) Sloping Tower
of Pisa (Built on Sand)
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Analogy
Bad examples
Tower of Babylon (Sign for Megalomania) Cathedral
of Beauvais (Partial Collapse) Sloping Tower of
Pisa (Built on Sand) Tacoma Bridge (Free
Oscillation Problem)
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Analogy
Bad examples
Tower of Babylon (Sign for Megalomania) Cathedral
of Beauvais (Collapse) Sloping Tower of Pisa
(Built on Sand) Tacoma Bridge (Free Oscillation
Problem) Congress Hall (Bad Ferro-Concrete) and
some others round the globe
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Analogy

• Consequences for the Education of Architects
• History of Architecture
• Design and Modeling
• Statics and Construction
• Industrial Production
• ...

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Introduction

• Goals of this Course
• Constructing efficient small and large systems
• Decomposing systems into subsystems and modules
• Understanding main problems around Concurrency
• Basic understanding of Hard-/Software-Interaction
  
• Distinguishing between Mechanisms and Policies
• Improving future systems (apply what you have
  learned!)

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Introduction
Tentative Schedule of this Course Hardware
Review Overview, Motivation, Problems Threads and
Concurrency Data and Buffering Scheduling Communi
cation and Networks Real-Time Systems Distributed
Systems Protection and Security
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Introduction
Literature (1) General Textbooks Bacon, J.
Concurrent Systems, Addison-Wesley, 1998 Bass,
L. Software Architecture in Practice,
A-W,1998 Davis, W. Operating Systems,
Addison-Wesley, 2001 Nehmer, J Grundlagen
moderner Betriebssysteme, dpunkt, 2001 Rising,
L. A System of Pattern, Wiley, 1996 Shaw, M.
Software Architecture, Prentice Hall, 1996 Shay,
W. An Introduction to Operating Systems, P H,
1993 Silberschatz, A. Operating Systems
Concepts, A-W, 1998 Stallings, W. Operating
Systems, Prentice Hall, 2001 Tanenbaum, A.
Modern Operating Systems, P H, 2001 Wettstein,
H. Systemarchitektur, Carl Hanser, 1993
31
Introduction
Literature (2) Specific Textbooks Beck,,
M. Linux Kernel Internals, A-W, 1998 Bovet,
D. Understanding the Linux Kernel, OReily,
2000 Leffler, S. The Design and Implementation
of the 4.3BSD Unix Operating System,
Addison-Wesley, 1996 Mohr, J. SCO Companion
The essential Guide to Users and System
Administrators, P H, 1997 Pham,
D. Multithreaded Programming with Windows NT, P
H, 1996 Solomon, D. Inside Windows NT,
Microsoft Press (2nd ed.), 1998 Tanenbaum, A.
Operating Systems Design and Inplementation,
Minix, P H, 1997 Vahalia, U. Unix Internals,
The New Frontiers, P H, 1996
32
Introduction
System Information on the Web
http//www.williamstallings.com/OS4e.html (other
slides and student information) http//joda.cis.t
emple.edu/courses-os.html (many courses on OS all
over the world) http//www4.informatik.uni-erlang
en.de/Lehre http//wwwagss.informatik.uni-kl.de/L
ehre
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Introduction
Style of this Course Lecture Open
Discussions We expect many ?!s from
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Introduction
What does System Architecture mean?
System something systematic (well, more or
less) There are different kinds of systems like

• Biological Systems (plants, animals, humen)
• Social Systems (insurance, pension)
• Economic Systems (market, stock exchange)
• Technical Systems (aqueduct, engines, tv etc.)
• Scientific Systems (system of chemical
  elements)
• Mobile Systems (cars, railways, rockets etc.)
• Hardware/Software Systems, e.g.
• general operating systems
• specialized (custom) control systems

35
Introduction
Central point of any computer system
Tasks Threads Coroutines Modules Procedures Statem
ents
Documents Windows Symbols Stacks Heaps Arrays
Structures Variables
Application
36
Introduction
What does System Architecture mean?
Architecture in general something beautiful
and elegant something comfortable
something useful discipline
how to design build an architecture
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Introduction
What does System Architecture mean?
System Architecture Something

• Understandable (for you)
• Explainable (for us)
• Correct (fulfilling the specifications)
• Robust (for system administrators)
• Reusable (for companies)
• Efficient (for users)
• Secure (for owners and users)
• Structured (for designers)
• Scalable (for future applications)
• Modularized (for programmers)

38
Introduction
Counterexamples
Denver Airport Luggage Control System Financial
System of London Stock Exchange Ariane 5 Airbus
Control System and some more witty failures like
the Mars Pathfinder Problem
?