what is difference between multitaskng and scheduling in real time os

Discussion in 'General Electronics Chat' started by vead, May 5, 2014.

  1. vead

    Thread Starter Active Member

    Nov 24, 2011
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    multitasking - the ability to execute more then one task at same time

    Q1) Is it correct definition for multitasking?

    task has three state
    running-executing on cpu
    ready-read to be execute
    waiting - waiting for execution

    If we have two task running at same time, both task can not be executed at same time so one of them will be delayed , one task will be wait another task will be execute

    Q2) one task will be wait another task will be execute but what decide that which one will be execute first and which one will be wait?

    I am confused about what is multitasking and scheduling
     
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
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  3. vead

    Thread Starter Active Member

    Nov 24, 2011
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    check out this definition
    kernel -kernel is part of operating system that provide basic service to application software running on processor

    multitasking - multitasking is process where one or more task run at same time on same single processor

    scheduling- scheduling is process by which operating system decide which one task will be perform first on processor

    please correct me If I am wrong
     
  4. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    Minor nit-picking points...

    multitasking - multitasking is process where one or more task appear to run at same time on same single processor

    scheduling- scheduling is process by which operating system decide which one task will be next on processor. More generally, scheduling determines the order in which tasks are executed.
     
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  5. vead

    Thread Starter Active Member

    Nov 24, 2011
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    type of scheduling
    First come First serve - task are executed on first come first serve basis
    shortest Job first - task execute first which take minimum time to execute
    priority based - each task has priority , higher priority task will be executed first

    which type of scheduling , rtos support
     
  6. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    RTOS support does not imply a specific type of scheduling. Different OS kernels may use different scheduling algorithms. The three you listed are not necessarily the only ones. Have you reviewed the Wikipedia article on scheduling?
     
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  7. vead

    Thread Starter Active Member

    Nov 24, 2011
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    real time os designer design scheduling algorithms.
    Different OS kernels may use different scheduling algorithms

    First come First serve -
    shortest Job first -
    priority based -

    Q) can one kernel support three scheduling algorithms ?

    Q) does one kernel support only one scheduling algorithms ?
     
  8. vead

    Thread Starter Active Member

    Nov 24, 2011
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    memory management for operating system

    how to write definition

    memory management is part of operating system that is used to store data
    memory management is function of operating system that is use to store data

    memory management is process of operating system that is uesd to store data
     
  9. Papabravo

    Expert

    Feb 24, 2006
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    In order to define memory management for an operating systems you start with an inventory of resources. Then you proceed to the methods and procedures for allocating, managing, and recovering blocks of various kinds of memory as they are needed, used, and returned.
     
  10. vead

    Thread Starter Active Member

    Nov 24, 2011
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    thats my confusion I know about memory but how to define memory with management
     
  11. Papabravo

    Expert

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    I'm not clear on what your question implies. Are you looking for a definition that would allow you to implement memory management or are you looking for a definition to input to some kind of simulation tool, or something I can't even imagine.
     
  12. vead

    Thread Starter Active Member

    Nov 24, 2011
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    I am asking definition what is memory management in operating system
     
  13. Papabravo

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    Feb 24, 2006
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    It is a system application that allocates blocks of memory to a process in such a way that only that process and the operating system can read and write to those blocks. Access to them is denied to all other processes except by well defined process communication methods. When a process is done with a memory block, it releases that block back to the pool of free blocks and the operating system can allocate it to another process.

    Are you seriously telling me you could not find this on your own?
     
  14. vead

    Thread Starter Active Member

    Nov 24, 2011
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    I found some definition but I was confused about management I mean what is management for operating system

    memory management
    I/o management
    file management

    I don't know how to write correct definition for above

    Q1 Is it process, function or part of operating system ?
     
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