htop Process Monitoring and Troubleshooting by Libor Benes (Dr. B)

htop Process Monitoring and Troubleshooting is a Firefox sidebar that provides instant, offline access to everything you need to understand and use the interactive process viewer htop.

htop is the modern, feature-rich process monitor for Linux, macOS, and other Unix systems. It displays running processes in a colorful, scrollable list with per‑core CPU meters, memory and swap graphs, and a rich set of interactive commands.

This Firefox extension is a pure reference guide – it does not run htop itself, but it puts all the essential knowledge right beside your browser workflow.

Content Coverage:
• Header Meters
Color KeyCPU bars (blue=low‑priority, green=normal, red=kernel, aqua=guest) and Memory/Swap bars (green=process memory, blue=buffers, orange=cache).

• Column Purpose and Interpretation
Detailed explanations of PID, USER, PR/PRI, NI, VIRT, RES, SHR, S, %CPU, %MEM, TIME+, Command.

• Monitoring Features
Tree view (F5), search/filter (F3/F4), setup (F2), and tagging (Space, c).

• Keyboard Shortcuts
All major shortcuts with clear key‑cap styling.

• Common Monitoring Patterns
Quick‑glance patterns (e.g., “High red CPU + high load → kernel bottleneck”).

• Troubleshooting Scenarios and Advice
15+ real‑world cases - high kernel usage, memory pressure, zombie processes, I/O bottlenecks, memory leaks, unexpected root processes, and more – each with actionable steps.

• Deep Dive: Output Analysis
How to combine columns (e.g., PID+%CPU+TIME+) and integrate with external tools like iotop, strace, and perf.

• Safe Actions and Best Practices
Responsible process management: SIGTERM before SIGKILL, tagging, using tree view, and more.

Target Audience:
• System administrators & site reliability engineers (SRE).
• Developers debugging performance issues.
• Incident responders and forensic analysts.
• Students learning Linux/Unix system monitoring.
• Anyone who occasionally uses htop and needs a quick cheat sheet.

Use Cases:
• Quickly recall what a column means while troubleshooting a high‑CPU process.
• Understand the color bars in the header meters at a glance.
• Learn keyboard shortcuts without leaving the browser.
• Step through a troubleshooting scenario (e.g., “Many 'D' states + high load”) with concrete advice.
• Keep a reference open alongside a terminal or documentation.

Features:
• Comprehensive coverage of all major htop concepts.
• Compact, scannable card‑based layout.
• Dark theme matching the original htop aesthetics.
• No external dependencies – pure HTML/CSS, inline style.
• Responsive design that fits perfectly in Firefox’s sidebar.

Security & Privacy First:
• No permissions requested – the extension does not access your data, network, or clipboard.
• No data collection – explicitly declared in the manifest with "required": ["none"].
• No telemetry, no external requests, no third‑party code – everything is embedded locally.
• Safe DOM construction – only createElement, textContent, createTextNode; no innerHTML or eval.
• Manifest v2 – compatible with current Firefox standards.

Technical Specs:
• Compatibility: Firefox 140.0+ (desktop only).
• Runtime memory: ~17 KB (manifest and HTML file).
• Download size: ~41 KB (including README).
• Performance: Instant load, no JavaScript processing.

Whether you’re a seasoned sysadmin, a developer tracking down a CPU spike, or a student learning the internals of process management, htop Process Monitoring and Troubleshooting puts a complete reference guide right where you need it – in your sidebar.