MemoryEngine

This project implements a memory management engine that handles paging and virtual memory. The system simulates a computer's memory management unit, dealing with both main memory and virtual memory, and executes various commands related to process management and memory operations.

Features

• Memory allocation for processes
• Paging system implementation
• Virtual memory management
• Process execution simulation
• Memory swapping (swap-in and swap-out operations)
• Page table management
• LRU (Least Recently Used) replacement algorithm

Key Components

1. Memory Initialization: Sets up main memory and virtual memory based on input parameters.
2. Process Management: Handles loading, running, and killing processes.
3. Paging System: Implements page tables and manages page allocation.
4. Virtual Memory Handling: Manages swapping between main memory and virtual memory.
5. Command Interpreter: Processes user commands for system operation.

Supported Commands

• load <filename1> <filename2> .. <filenameN>: Load executables into memory
• run <pid>: Execute a program
• kill <pid>: Terminate a program
• listpr: List all processes in memory
• pte <pid> <file>: Print page table entries for a process
• pteall <file>: Print all page table entries
• swapout <pid>: Move a process to virtual memory
• swapin <pid>: Move a process to main memory
• print <memloc> <length>: Print values in physical memory
• exit: Terminate the system

Implementation Details

• Written in C/C++
• Uses LRU algorithm for page replacement
• Handles both main memory and virtual memory
• Simulates process execution with basic arithmetic operations

Usage

Compiling :

g++ -o memoryEngine main.cpp Process.cpp MemoryManager.cpp

Executing :

./memoryEngine -M <main_memory_size> -V <virtual_memory_size> -P <page_size> -i <input_file> -o <output_file>

Input and Output Files

Input Files

1. Executable Files:

   • Contains programs to be loaded and executed by the memory management system.
   • Format:
     • First line: Size of the executable in KB
     • Subsequent lines: Commands to be executed
   • Supported commands in executables:
     • add x, y, z: Add contents of addresses x and y, store in z
     • sub x, y, z: Subtract contents of address y from x, store in z
     • print x: Print value at address x
     • load a, y: Store value 'a' at address y

2. System Command Input File:

   • Contains a sequence of system commands to be executed by the memory manager.
   • Supported system commands:
     • load <filename1> <filename2> .. <filenameN>
     • run <pid>
     • kill <pid>
     • listpr
     • pte <pid> <file>
     • pteall <file>
     • swapout <pid>
     • swapin <pid>
     • print <memloc> <length>
     • exit

Output Files

1. Main Output File:

   • Contains the results and messages from executing the system commands.
   • Includes:
     • Process loading confirmations
     • Execution results of programs
     • Error messages
     • Listings of processes in memory
     • Results of memory print commands

2. Page Table Entry Files:

   • Generated by pte and pteall commands.
   • Contains page table information for specified processes.
   • Format includes:
     • Date and time of the command execution
     • Process ID
     • Logical page numbers and corresponding physical page numbers