Concurrent and Distributed Systems

459 Pages·2015·12.93 MB·English

Welcome to COMP2310/6310 – Concurrent and Distributed Systems
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COMP2310 Lecture 1: Introduction 2013 • × 1
The Growing Importance of Concurrent and Distributed Systems
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computer systems are inherently concurrent
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computer-based services are inherently distributed
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advent of multicore/manycore chips, exascale
computing, mobile computing, cloud computing,
ubiquitous computing
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to what extent must CDS concepts and
techniques be treated explicitly in the
profession?
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followup curriculum in CDS
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COMP3300/6330 Operating Systems*
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COMP3310/6331 Computer Networks
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COMP3320/6464 High PerfSci. Computation
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COMP4330/6430 Parallel Systems*
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COMP4330/6433 Real-Time and Embedded Systems*
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COMP4340/8320 Multicore Computing*
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COMP2310 Lecture 1: Introduction 2013 • × 2
Course Contact
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course web site: http://cs.anu.edu.au/courses/comp2310
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course coordinator & lecturer:
Peter Strazdins, CSIT N219, 6125-5140, comp2310@cs
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course tutors: Brian Lee, Beau Thompson, and Peter Strazdins
(Computer Systems Group)
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forums accessible by StReAMS:
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Announcements: postings from course staff only
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Discussion: for your use (note the rules!)
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COMP2310 Lecture 1: Introduction 2013 • × 3
Course Schedule
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lectures: three hours per week
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Concurrency: based on Chapters 2–8 and 10 of [Magee&Kramer ]
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Processes and Threads, Concurrent Execution, Shared Objects & Interference,
Monitors & Condition Synchronization, Deadlock, Safety and Liveness,
Model-based Design, Message Passing; Architectures: Operating Systems
(+communication)
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Distributed Systems: based on Chapters 1–4, 7, 14–18 of [Coulouris&al ]
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Overview, Networks, Distributed Time and State, Agreement, Transactions,
Replication
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practicals (supervised tutorial/laboratories): 8 (formal) and (3×0 5) informal
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→ register NOW via http://cs.anu.edu.au/streams
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important to come prepared! will contain examinable material!
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assignments: 2
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more details on the course schedule page
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COMP2310 Lecture 1: Introduction 2013 • × 4
Course Assessment
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see the assessment web page
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Assignments: due weeks 7 (18%) and 12 (12%)
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note plagiarism issues and unacceptable vs acceptable collaboration:
producing a solution with the aid of another’s solution is cheating!
working in close groups throughout is dangerous and is unfair to others!
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Practical Session Quizzes and Exercises: 10%
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best 5 of 2% marks in 8 sessions
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note: no extensions! (you should plan to attend all)
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Mid-Semester Exam: week 8 (Concurrency)
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Final Exam: 50%
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3 hours, 1 page A4 notes (both sides, printed or hand written), no calculator
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former exam papers available from course web page;
note that not all questions are still applicable
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COMP2310 Lecture 1: Introduction 2013 • × 5
Approach for Concurrent & Distributed Systems
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emphasis is on general principles, design (modelling - new!), and systematic
implementation
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modelling includes Finite State Processes, with structure diagrams
BSEMA(Init=0) = BSEMA[Init℄,
< >
−
BSEMA[v:Int℄ = ( when (v Max) up BSEMA[v+1℄
> >
| − −
when (v 0) down BSEMA[v 1℄ ).
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emphasis is on contemporary practice rather than classical theory
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CDS are part of our everyday life but reliable computer implementation requires
sound understanding of various complex and subtle concepts!
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a serious approach is needed for succeeding in this course:
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engagement throughout is essential!
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especially coming prepared, attending all tutorial / laboratories and
completing the (main) exercises
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don’t be deceived by the terseness of FSP;
it can be subtle and takes time to master!
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need to use the ltsatool (& study resulting LTS diagrams)
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reading the textbooks, particularly [Magee&Kramer ]) is needed for follow-up
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COMP2310 Lecture 1: Introduction 2013 • × 6
Mastering Concurrent & Distributed Systems
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Describe the concepts involved in the construction of CDS.
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‘Speak the language” of concurrent modelling, design and programming.
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explain the ideas & issues; explain and analyze key algorithms in CDS
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be fluent with 1 modelling language and 2 programming languages
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Select appropriate modelling techniques and mechanisms and apply them to the
solution of problems in CDS
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model problems in FSP and analyze for required properties
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Select the appropriate programming language and environment for the task at
hand.
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understand the strengths and weaknesses of approaches and languages
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Write scalable, concurrent modules which show the intended and predictable
behaviors. Includes monitors!
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Analyze and debug small to medium scale concurrent programs.
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design & implement non-trivial solutions in Java and C
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COMP2310 Lecture 1: Introduction 2013 • × 7
Introduction to Concurrency
Overview:
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what is a concurrent program?
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concurrent and distributed software
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why concurrent programming?
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why is it important to get it right?
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(Magee & Kramer’s) Cruise Control System
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models and modeling the Cruise Control System
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programming practice in Java
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objective of the concurrency module; and the book!
(the reminder of these slides including graphics are a modified version of the slides from Ch1 of Magee &
Kramer: Concurrency)
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COMP2310 Lecture 1: Introduction 2013 • × 8
What is a Concurrent Program?
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a sequential program has a single thread of
control.
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a concurrent program has multiple threads of
control allowing it to:
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perform multiple computations in parallel
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to control multiple external activities
which occur at the same time
The proper co-ordination of these threads
and maintaining the integrity of shared data
form the major challenges of concurrent
programming!
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COMP2310 Lecture 1: Introduction 2013 • × 9
Concurrent and Distributed Software
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interacting, concurrent
software components of a
system:
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single machine → shared
memory interactions
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programming model:
threads API or message
passing
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multiple machines → network
interactions
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programming model:
message passing (or
derivatives, e.g. remote
method invocation)
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forms a distributed system
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COMP2310 Lecture 1: Introduction 2013 • × 10