Vinay Arora

CSED

Threads

Organized By: Vinay Arora

Assistant Professor

CSED, TU

Vinay Arora

CSED

Disclaimer

This is NOT A COPYRIGHT MATERIAL

Content has been taken mainly from the following books:

Operating Systems Concepts By Silberschatz & Galvin, Operating Systems: Internals and Design Principles By William Stallings

www.os-book.com

www.cs.jhu.edu/~yairamir/cs418/os2/sld001.htm

www.personal.kent.edu/~rmuhamma/OpSystems/os.html

http://msdn.microsoft.com/en-us/library/ms685096(VS.85).aspx

http://www.computer.howsttuffworks.com/operating-system6.htm

http://williamstallings.com/OS/Animations.html

Etc…

Vinay Arora

CSED

Thread

� Application - Set of Multiple Processes

� Process – An Executable File (.exe)

� Each PROCESS has its own Address Space, CPU Quota, Access to

Hardware Resources and Kernel Resources

� THREAD – Function Present within Executable File

� Each THREAD has its own PC, Stack , Registers

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Process Thread View

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Process View

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Thread View

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Processes & Threads

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User Space & Kernel Space

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Multicore Programming

� Multi-Core Systems putting pressure on programmers, challenges include

� Dividing activities

� Balance

� Data splitting

� Data dependency

� Testing and debugging

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Concurrent Execution on a Single-core

System

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Concurrent Execution on a Multi-core

System

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Pure User Level

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Pure Kernel Level

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Combined

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Combined Threads

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Single & Multi Threaded Process

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Benefits

� Responsiveness

� Resource Sharing

� Economy

� Utilization of MP Architectures

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User Thread & Kernel Thread

� User Thread - Thread Management done by User-Level Threads Library

� Kernel Thread - Supported by the KERNEL

� Examples

� Windows XP/2000

� Solaris

� Linux

� Tru64 UNIX

� Mac OS X

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Thread Library

� Three Primary Thread Libraries:

� Java Threads

� Pthreads

� Win32 Threads

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Multi Threading Models

� Many-to-One

� One-to-One

� Many-to-Many

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Many-to-One Model

� Many User-Level Threads mapped to Single Kernel Thread

� Examples:

� Solaris Green Threads

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One-to-One Model

� Each User-Level Thread maps to KERNEL THREAD

� Examples

� Linux

� Solaris 9 and later

� Windows NT/XP/2000

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Many-to-Many Model

� Allows many User Level Threads to be mapped to many Kernel Threads

� Allows the Operating System to create a sufficient number of Kernel

Threads

� Windows NT/2000

Vinay Arora

CSED

Thnx…