memory management - Simulation of dynamic partition allocation

Second course assignment of operating system - Simulation of dynamic partition allocation

Project requirements

Assuming the initial state , The available memory space is 640K, And there is the following request sequence , Please use the first adaptation algorithm and the best adaptation algorithm to allocate and recycle memory blocks respectively , It also shows the free partition chain after each allocation and recycling .

Project purpose

• data structure 、 Allocation algorithm
• Deepen the understanding of dynamic partition storage management mode and its implementation process

development environment

• development environment : Windows 10

• Development software :

  1. Visual Studio Code1.34.0
  2. WebStorm2019.1.1.WS-191.6707.60

• development language : html, javascript, css, jQuery

• Main reference block content :

  <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
  

Project structure

│  README.md   
│   Simulation of dynamic partition allocation _ Design scheme Report .md   
│   Simulation of dynamic partition allocation _ Design scheme Report .pdf   
│  
├─Resource   
│      memory.png   
│      
└─src   
    │  Dynamic partition allocation.html   
    │  
    └─static  
        ├─css   
        │      range.css   
        │      style.css   
        │      
        └─js   
                clear.js   
                nextAssingment.js   
                randColor.js   
                RangeSlider.js   
                select.js   

Operation instructions

• Double click the directory src Under the Dynamic partition allocation.html file , And open... In the browser , After opening, the interface is shown in the figure below

• Choose the dynamic partition allocation algorithm you want to simulate *( First adaptation algorithm / Best fit algorithm )*

• Adjust the slider to change the current memory size *( The length of the simulated chain space above will change dynamically with the sliding of the sliding bar )*

• Click on next step Scheduling jobs

• The simulated memory above will show the free partition chain after each allocation and recycling *( Different colors for different jobs , To distinguish the location distribution of different jobs in memory )*

• The log information below will show the job apply / Release Etc

• Click on Clear Memory It will clear all contents of jobs and log information in memory , At this time, you can adjust the memory space again , And the dynamic partition allocation mode is simulated again

Systems analysis

• First adaptation algorithm

  • Algorithm logic : Record the space used in the current memory , At the same time, record the available space in the current memory ( And list them in order of physical location )

     If the current job needs to apply for memory space  =>  The size of the first free block is larger than the required space  =>  Mark the occupied memory empty as used  =>  Adjust the size and position of the free block accordingly 
    

• Best fit algorithm

  • Algorithm logic : Also record the space used in the current memory , At the same time, record the available space in the current memory ( And list them by physical capacity )

     If the current job needs to apply for memory space  =>  Find the physical block with the smallest current capacity and meeting the current application requirements  =>  Mark the occupied memory empty as used  =>  Adjust the size and position of the free block accordingly 
    

The system design

Interface design

1. Integral design

Function realization screenshot display

First adaptation algorithm

Best fit algorithm

Out of memory

Choose a dynamic partition allocation algorithm

Adjust the slider to dynamically change the memory size

Click next to schedule the job

Log information