L2K (Load 2 KeyboardLED) v3.3.1

Ultra-lightweight Linux system monitor. Gone are the complex GUIs—we use LEDs for display.

look GIF 👇

No LEDs? You’ve got three on your keyboard. No keyboard backlights? Try your NIC or disk indicators—any kernel-managed LED will do.

If you lack even those, you're on your own.

Features

• Real-time Monitoring：Track CPU, RAM, and Disk utilization (multi-disk support included).
• Flashing: LED indicators flash based on system load.
• Customizable: Customize LED mapping, thresholds, and flash frequency via /etc/l2k.conf .
• Silent Mode：Runs quietly in the background by default.
• i18n Support: Supports both Chinese and English.

Installation

Download install.sh. Run chmod +x install.sh and sudo ./install.sh [optional installation directory].

Usage

Running

Root privileges are required to write to the LED devices under /sys/class/leds/ .

By default, the tool runs in background mode.

Supported Command Line Arguments:

• -f Run in foreground mode.
• -h Show help message.
• -v Display version information.

To stop the program, use sudo pkill l2k . (We have a graceful shutdown, but how "graceful" it actually is, nobody knows.)

Configuration

The configuration is stored at /etc/l2k.conf.

Lines starting with # are ignored as comments.

Line 1: Contains two integers.

• Threshold (0-100): The system load percentage at which the LED stays solid (always on).
• Flash Interval (at 1% load): The base flash period in ticks (1 tick = 10ms).

Remaining lines: Each line contains 2 to 3 space-separated strings, representing:

• LED Name: The system will search for this automatically (e.g., you can use "numlock").
• Metric: Select from CPU, RAM, or DISK.
• Disk Name: (Optional) e.g., "sda", "sdb". This field is only effective when the Metric is set to DISK.

Compilation

Requires C++17 on Linux.

g++ --std=c++17 l2k.cpp -o l2k

If i18n.h is missing, the tool will default to English.

Warning: Lacks thorough testing!!!
You’re still helpful, even if it's just for translations.
Pending: Native English speakers (or fluent speakers) needed to rewrite i18n and README_EN.md.
Pending: Translation: Translated by Gemini-3-Flash; verification required.