Distributed Computing Systems - PowerPoint PPT Presentation

Distributed Computing Systems

Hugh C. LauerAdjunct Professor

(Slides include materials from Operating System Concepts, 7th ed., by Silbershatz, Galvin, & Gagne and from Modern Operating Systems, 2nd ed., by Tanenbaum)

Introduction

• Introduction to CS-4513
• What is “Distributed Computing”
• An example of a distributed computation
• Networks
• Assignment of Project #1

Introduction

• Continues CS-3013, Operating Systems
• File Systems
• One lecture in C-Term CS-3013
• No coverage in A-Term CS-3013
• Networks & Communication
• Computations that run on more than one machine
• Close together
• Far apart
• Internet and World Wide Web

Introduction

• Textbooks:– You should own or have access to one of the following from CS-3013
• Operating Systems Concepts, 7th ed, by Silberschatz, Galvin, and Gagne, John Wiley and Sons, 2005
• Modern Operating Systems, 2nd edition, by Andrew S. Tanenbaum, Prentice Hall, 2001
• Supplemental Text:–
• Distributed Systems: Principles and Paradigms, Tanenbaum and Van Steen, Prentice-Hall, 2007
• Course Information:
• http://www.cs.wpi.edu/~cs4513/d07/

Introduction

• Prerequisites:
• CS-3013, Operating Systems or equivalent
• C and C++ programming, esp. low level programming
• Data structures
• Unix/Linux user experience and access
• Computer Organization
• 1st reading assignment: any of the following
• Silbershatz, §16.1-16.4
• Tanenbaum, §8.3
• Tanenbaum & Van Steen, Chapter 1

Introduction

Goddard Hall 227

9:00 – 10:50 AM

Tuesdays and Fridays thru May 1

No class on April 17

14 classes total

Exams

Mid-term on April 3

Final on May 1

Unannounced Quizzes

May occur at any time

May be at beginning, middle, or end of class

Mobile Phones, pagers, laptops, and other devices OFF during class

~4 Programming Projects

Fossil Lab

Office Hours

Adjunct Office, Fuller 239

by appointment, or

Normally ½ hour before and after class

Teaching Assistant

Choong-Soo Leeclee01 **at** cs.wpi.edu

Contact

<Professor’s last name> @ cs.wpi.edu

Adjunct office phone:(508) 831-6470 (shared, no messages)

Introduction

• Grading
• Exams – 35%
• Programming Projects (~4) – 35%
• Class participation, homework, & quizzes – 30%
• Unless otherwise noted, assignments are to be completed individually, not groups
• Late Policy – 10%/day
• But contact Professor for extenuating circumstances
• WPI Academic Honesty policy

Introduction

• Is this course the capstone for a Minor in CS?
• Anyone needing a project for BS & MS credit?

Introduction

• There are no “stupid” questions.
• It is a waste of your time and the class’s time to proceed when you don’t understand the basic terms.
• If you don’t understand it, someone else probably doesn’t, either.

Introduction

• Who are you?
• Name, year, degree, major
• Work experience in computing, etc.?
• C & C++ experience
• Other programming experience
• Why CS-4513 – Distributed Computing Systems?
• Anything else relevant?

Introduction

• Ph. D. Carnegie-Mellon 1972-73
• Dissertation “Correctness in Operating Systems”
• Lecturer: University of Newcastle upon Tyne, UK
• 30+ years in research and development in industry in USA
• Research and system topics
• Operating Systems
• Proofs of Correctness
• Computer Architecture
• Networks and Distributed Computing
• Real-time networking
• 3D Volume Rendering
• Surgical Simulation and Navigation
• …

Introduction

• University of Newcastle
• Systems Development Corporation
• Xerox Corporation (Palo Alto)
• Software Arts, Inc.
• Apollo Computer
• Eastman Kodak Company
• Mitsubishi Electric Research Labs (MERL)
• Real-Time Visualization
• Founded and spun out from MERL
• Acquired by TeraRecon, Inc.
• SensAble Technologies, Inc.
• Currently: CTO, Dimensions Imaging, Inc.

Introduction

• 21 US Patents
• Two seminal contributions to CS
• Duality Hypothesis of Operating System Structures (with Roger Needham)
• First realization of opaque types in type-safe programming languages (with Ed Satterthwaite)
• VolumePro™
• World’s first 2D, 3D, and 4D volume rendering system at interactive speeds for medical, seismic, and scientific visualization

Introduction

• Interactive volume rendering of 3D data such as
• MRI scans
• CT scans
• Seismic scans
• Two generations of ASICs, boards, software
• VolumePro 500 – 1999
• VolumePro 1000 – 2001
• CTO, Chief Architect of VolumePro 1000
• 7.5-million gate, high-performance ASIC
• 109 Phong-illuminated samples per second

Introduction

Introduction

Class Discussion

What is Distributed Computing?

Introduction

• Collection of computers that are connected together and (sometimes) interact
• Many independent problems at same time
• Similar
• Different
• Or …
• One very big problem (or a small number)
• Computations that are physically separated
• Client-server
• Inherently dispersed computations

Introduction

• Many independent problems at same time
• Similar — e.g., banking & credit card; airline reservations
• Different — e.g., university computer center; your own PC
• Or …
• One very big problem (or a few)
• Computations that are physically separated
• Client-server
• Inherently dispersed computations

Introduction

• Many independent problems at same time
• Similar — e.g., banking & credit card; airline reservations
• Different — e.g., university computer center; your own PC
• Or …
• One very big problem (too big for one computer)
• Weather modeling, finite element analysis; drug discovery; gene modeling; weapons simulation; etc.
• Computations that are physically separated
• Client-server
• Inherently dispersed computations

Introduction

• Many independent problems at same time
• Similar — e.g., banking & credit card; airline reservations
• Different — e.g., university computer center; your own PC
• Or…
• One very big problem (too big for one computer)
• Weather modeling, Finite element analysis; Drug discovery; Gene modeling; Weapons simulation; etc.
• Computations that are physically separated
• Client-server
• Dispersed – routing tables for internet; electric power distribution.

Introduction

• Same spectrum applies to multiprocessor systems
• Much more tightly coupled that traditional “distributed systems”
• Some differences
• “Multiprocessor systems”
• Usually under same management
• Very fast communication
• “Distributed systems”
• Sometimes not under same management
• Slower communication

Introduction

• When you change the operating point of a system by an order of magnitude …

… you introduce qualitative changes in how to approach problems

Introduction

• An inherently distributed computation
• I.e., parts of the computation must occur at physically separate locations
• Under separate administrations
• Internet routing tables

Introduction

• A vast collection of independent computers
• ~ 600  106
• All connected together
• Any computer can send a message to any other
• Messages broken up into little packets
• Question: how do packets find their way to destinations?

Introduction

Introduction

• Each node “knows” which networks are directly connected to it.
• Each node maintains table of distant networks
• [network #, 1st hop, distance]
• Adjacent nodes periodically exchange tables
• Update algorithm (for each network in table)
• If (my distance to network>neighbor’s distance to network + my distance to neighbor), then …
• … update my table entry for that network so that neighbor is first hop.

Introduction

• All nodes in Internet maintain reasonably up-to-date routing tables
• Rapid responses to changes in network topology, congestion, failures, etc.
• Very reliable with no central management!

Introduction

• The routing algorithm is inherently distributed
• Different parts execute in physically separated locations
• Only nearby nodes “know” whether
• Neighbors are up or down
• Networks are congested or not

Introduction

• Network management systems
• Monitoring health of network (e.g., routing tables)
• Identifying actual or incipient problems
• Data and statistics for planning purposes

Introduction

Questions?

Next TopicProgramming Project

Introduction