Chapter1 ' Operating System Fundamentals

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Chapter1 . Operating System Fundamentals

• Overview
• Evolution of Modern OS
• Centralized OS
• NOS
• DOS
• Cooperative Autonomous systems
• Distributed Algorithm

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1.0 Overview

• Advanced in computer and communication
  technologies
• Distributed systems
• Multiple computers
• Communication channels
• Cooperative works(applications)
• Distributed software
• Distributed operating system vs. Distributed
  systems
• Multiprocessor
• Network architecture
• In this chapter
• Traditional operating systems
• Modern operating systems
• Distributed OS and Distributed system
• Distributed algorithms

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1.1 Evolution of Modern Operating Systems

• Operating systems
• A set of software modules to assists programmers
  ( that is, interfacing between application
  programs and system hardware) in enhancing
  systems efficiently, flexibility, and robustness
• Multiplexing and scheduling of processor(s)
• Coordinating the interacting processes
• Managing system resources(I/O, memory, data
  files)
• Enforcing access control and protection
• Maintaining system integrity
• Performing error recovery
• Proving interface to the users
• For structuring above primary functions
• System service High-level functions
• KernelSystems essential functions advanced in
  computer and communication technologies

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1.1 Evolution of Modern Operating Systems

• A Layer-structure computer system
• Users viewpoint
• System services
• Extended machine
• Systems viewpoint
• Administrators viewpoint
• Resource manager

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1.1 Evolution of Modern Operating Systems

• Evolution of modern operating systems
• Centralized operating system
• Virtuality(resource management extended
  machine)
• Network operating system
• Interoperability(resource sharing)
• Distributed operating system
• Transparency(A single view system of multiple
  systems)
• Cooperative autonomous system
• Cooperative work with Autonomicity
• A Spectrum of OS
• Decreasing degree of Hardware and Software
  coupling
• Figure 1.2 in page 5
• A comparison of features in modern OSs
• Table 1.1 in page 6

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1.2 Centralized Operating System Overview

• Traditional OS
• Single/multiprocessor architectures
• Tightly coupled systems
• Resource(ex. Main Memory) sharing internally
• Interprocessor/interprocess communication
• Through memory sharing and process interrupts
• Major functions of a centralized OS
• Table 1.2 in page 8

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1.2 Centralized Operating System Overview

• OS structure
• Two traditional approaches
• Horizontal partitioning
• lager disjoint components(grouped module)
• Vertical partitioning
• Interaction between layers
• Each layer with two interfaces
• Vertical and Horizontal partitioning of OS
• Figure 1. 3
• OS structuring methods
• Modulation
• Vertical Horizontal partitioning
• Client/server model(call in OS, message passing
  in DC)
• Minimal(micro) kernel
• Subsystem with API and SPI

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1.2 Centralized Operating System Overview

• Subsystem and Microkernel
• Microkernel
• To support application-oriented subsystems
• Microkenel architecture
• A hardware(platform) dependent minimal kernel
  A set of hardware independent executives(system
  services) with well defined API
• HAL or SPI for different platform
• Figure 1.4 in pages 10
• HAL(Hardware Abstraction Layer)
• Enhancing portability for low-level platforms
• SPI(Service Provider Interface)
• Providing extensibility for high-level
  applications
• Window NT system architecture
• Figure 1.5 in page 11

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1.2 Centralized Operating System Overview

• Managing Functions
• Resource Manager
• Processors/Processes management
• Procerssos scheduling
• Multiplexing
• multiprogramming, timesharing for the
  supports of
• interrupt-handling mechanism
• time-multiplex processor, space-multiplex
  memory
• Concurrent executing processes
• Processes interaction
• Interprocess communication
• relating to process synchronization
• Synchronization
• mutual exclusion
• condition coordination
• Scheduling

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1.2 Centralized Operating System Overview

• turnaround time, throughput
• static process scheduling, and dynamic load
  sharing and balancing
• Device(I/O) management
• Device driver, buffering, spooling
• Deadlock algorithm
• Deadlock prevention, avoidance,
  detectionsolution
• Memory management
• Memory allocation deallocation
• Logical to physical address mapping
• Virtual memory support(paging, segmentation)
• Page replacement algorithm
• Data(file) management
• File access sharing, concurrent control, data
  replication
• Protection security control algorithm

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1.3 Network Operating Systems(NOS)

• Network operating system
• Interoperability( for resource sharing) in a
  heterogeneous computer networks
• Providing transport service and
  application-oriented peer-to-peer process
  communication protocol
• Followed to ISO/OSI 7 layer RM
• High-level API
• Socket and Remote Procedure Call(RPC)
• Network applications(Servers for transport
  service)
• Remote login(terminal emulation)
• File transfer(ftp, rcp)
• Messaging(EDI, e-mail X.400, SMTP)
• Network browsing(WWW - URLs, html, databases)
• Remote execution(applets)
• Integration of transport service
• Figure 1.6 in page 16

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1.4 Distributed Operating Systems(DOS)

• Distributed operating system
• Transparency( for system services)
• In centralized OS
• Concurrency, location, access transparency
• In Distributed OS
• Parallelism, performance transparency
• Algorithms to implemented transparency
• Servers for supporting resource sharing and
  distributed processing(coordination of
  activities)
• Details in latter chapters
• Coordination of distributed processes
• Management of distributed resources
• Implementation of distributed algorithm
• Chapter3-5, 6-8, 9-13, respectively

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1.5 Cooperative Autonomous Systems

• CAS(Cooperative Autonomous Systems)
• Loosely coupled system(both in software and
  hardware)
• Fundamental difference between DOS and CAS
• Figure 1.7 in page 20
• Decomposition in Distributed systems
• Integration in Autonomous systems
• Figure 1.8 in page 21
• Decentralized CAS
• CSCW(computer support cooperative work)
• Groupware
• Distributed conferencing
• Model for distributed cooperative application
• Client/server model
• Object model
• CORBA and ODP
• Software bus(middleware, broker, or trader)

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1.6 Distributed Algorithms

• Needs of design and implementation of distributed
  algorithms
• Algorithm implementation gt DOS services
• Coordination of execution of concurrent process
• Called Protocols
• Interesting orders or rules for interacting
  process rather than perform computation
• Why do you study(need) the distributed algorithm
  comparing with the centralized algorithm
• Weakness or limitation of distributed system
• Algorithm changes due to message passing
• Lack of global system state information
• Consensus algorithms
• Distributed concurrency algorithm to avoid
  interference in resource sharing

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1.6 Distributed Algorithms Summary

• Coherency algorithm to maintain consistency for
  data replication
• Protocols for group communication in distributed
  applications
• Fault-tolerance algorithms for handling failure
  and recovery
• Real-time and distributed scheduling algorithms
• Summary
• Brief summary of OS structures
• Overview of traditional Oss
• Introduction of modern Oss
• NOS
• DOS
• Goals of Oss
• Virtuality, interoperability, transparency,
  autonomicity

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1.6 Distributed Algorithms

• Classification of Oss
• Centralized OS
• NOS
• DOS
• Autonomous systems
• Collection of OS(its software structuring)
• Modularization
• Partitioning
• Layering
• Achieving better extensibility and portability
  of OS
• Client/server model
• Subsystem
• Microkernel
• Traditional OS VS. DOS
• Traditional OS resource management
• DOS extended machine(system service)
  transparency

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1.6 Distributed Algorithms

• NOS
• Extension of Traditional OS
• Transport service to support interoperability for
  Resource sharing
• DOS
• Distributed processing Transparency
• Modern distributed systems
• Client/server model
• Object-oriented model
• ? developing cooperative autonomous
  systems(ODP,CORBA)
• Parts
• Part 1 discuss design and implementation of
  DOSs
• Chapter 2 DOS and algorithm concepts
• Chapter 3 System design and implementation
  issues
• Part 2 fundamental algorithms for managing DSs