Class notes --01 operating system, the operating system introduced

Class notes --01 operating system, the operating system introduced

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1.1 What is an operating system?

1. User perspective: OS is a control software
   1. Management Applications
   2. Application service
   3. Kill the application
2. Resource Management (manager angle)
   1. Peripheral management, resource allocation
   2. 
3. OS architecture level
   1. On the hardware, the application under
   2. Provide support services for the application software
   3. 
4. Internal components of the operating system (Kernel)
   1. CPU scheduling
   2. Physical Memory Management
   3. Virtual Memory Management
   4. File Memory Management
   5. Interrupt handling and device drivers
5. OS Kernel features:
   1. Concurrency (at a time, a plurality of programs are running)
      
      distinguished (parallelism): at a point in time, there are more programs running simultaneously
   2. Share ( "simultaneous" access, shared mutually exclusive)
   3. Virtual
      
      explanation: the use of multi-channel programming techniques, so that each user can feel the whole machine is exclusive

   4. Asynchronous (stop and go running program, but the results of the same operation)

      1.2, the operating system history and evolution?

      

      Comparative data parameters of each operating system

      

      Manual (no OS stage)

      Single-batch operating system

      

      Multi-channel batch operating system

      

      Sharing operating system

      

      PC operating system

      

      Distributed Operating Systems

      

      Operating system evolution (future trends: cloud direction)

      

      1.3, the operating system architecture

      Simple System: MS-DOS (1981-1994)

6. Does not distinguish between the monolithic kernel module
7. Written in assembly language

8. 

   Unix operating systems (1972)

9. C language

   Microkernel design: as much as possible to move the user space kernel function

   
   

10. Consideration: Performance Issues

    More extreme design: an outer core (Advantages: speed)

    

    Virtual machine monitor