Linux System Monitor

A real-time system monitoring application for Linux, built in C++. This project provides a terminal-based interface similar to htop that displays system information including CPU usage, memory utilization, and running processes.

Features

• CPU Monitoring: Real-time CPU utilization percentage for overall system and individual cores
• Memory Tracking: Current memory usage displayed as percentage and visual progress bar
• Process Information: Top 10 processes sorted by resource usage, showing:
  • Process ID (PID)
  • User
  • CPU percentage
  • RAM usage (MB)
  • Uptime
  • Command
• System Information: OS name, kernel version, system uptime
• Process Statistics: Total and running process counts
• Auto-refresh: Updates every second for real-time monitoring

Architecture

The project is organized into several key components:

• ProcessParser (src/process_parser.cpp): Parses Linux /proc filesystem to extract system and process information
• SysInfo (src/sys_info.cpp): Aggregates and manages system-level statistics (CPU, memory, uptime)
• Process (src/process.cpp): Represents individual process with its attributes
• ProcessContainer (src/process_container.cpp): Manages collection of processes and refresh logic
• ncurses Display (src/main.cpp): Terminal UI rendering using ncurses library
• Utilities (src/util.cpp, src/format.cpp): Helper functions for formatting and file I/O

Requirements

• Operating System: Linux (uses /proc filesystem)
• Compiler: C++17 compatible compiler (GCC 7+ or Clang 5+)
• Libraries:
  • ncurses library for terminal UI
  • CMake 2.6 or higher

Installing ncurses

On Ubuntu/Debian:

sudo apt install libncurses5-dev libncursesw5-dev

On Fedora/RHEL:

sudo dnf install ncurses-devel

Build Instructions

This project uses CMake and Make for building.

Available Make Targets

• make build - Compiles the source code and generates the executable
• make format - Applies ClangFormat to style the source code
• make debug - Compiles with debugging symbols enabled
• make clean - Removes the build/ directory and all build artifacts

Building the Project

1. Clone the repository:

git clone <repository-url>
cd System-Monitor-Project

2. Build the project:

make build

3. Run the monitor:

./build/monitor

The application will launch in your terminal and begin displaying real-time system information.

Implementation Details

Data Sources

The application reads system information from Linux /proc filesystem:

• /proc/stat - CPU statistics
• /proc/meminfo - Memory usage
• /proc/uptime - System uptime
• /proc/version - Kernel version
• /proc/[pid]/stat - Process-specific CPU and timing data
• /proc/[pid]/status - Process memory and user information
• /proc/[pid]/cmdline - Process command line

CPU Calculation

CPU utilization is calculated by measuring the difference in active and idle time between successive reads of /proc/stat, using the formula:

CPU % = 100 * (active_diff / (active_diff + idle_diff))

Process Monitoring

The application monitors all running processes and displays the top 10 by resource usage. Each process is updated every refresh cycle to show current CPU and memory consumption.

Project Structure

.
├── CMakeLists.txt          # CMake build configuration
├── Makefile                # Make targets for build automation
├── README.md               # This file
├── include/                # Header files
│   ├── constants.h
│   ├── format.h
│   ├── linux_parser.h
│   ├── ncurses_display.h
│   ├── process.h
│   ├── process_container.h
│   ├── process_parser.h
│   ├── processor.h
│   ├── sys_info.h
│   ├── system.h
│   └── util.h
└── src/                    # Source files
    ├── format.cpp
    ├── linux_parser.cpp
    ├── main.cpp
    ├── ncurses_display.cpp
    ├── process.cpp
    ├── process_container.cpp
    ├── process_parser.cpp
    ├── processor.cpp
    ├── sys_info.cpp
    ├── system.cpp
    └── util.cpp

License

This project is part of the C++ Bootcamp curriculum.