Disk Usage Skill

Analyzes disk space and filesystem usage on Linux systems.

Suggested Workflow

1. Run ./scripts/diskinfo.sh for a structured overview of mounts, block devices, and top directories.
2. Check df -h output for any filesystem above 80% usage.
3. Drill into high-usage mounts with du -h --max-depth=1 /mount to find large subdirectories.
4. Locate specific large files with find /path -type f -size +100M.

Commands Reference

Filesystem Overview

• df -h - Disk space usage for all mounted filesystems (human-readable)
• df -i - Inode usage (number of files)
• lsblk - Block device tree (disks, partitions)
• mount - Currently mounted filesystems

Directory Size Analysis

• du -sh /path - Total size of a directory
• du -h --max-depth=1 /path - Size of immediate subdirectories
• du -ah /path | sort -rh | head -20 - Largest files/directories

Finding Large Files

• find /path -type f -size +100M - Files larger than 100MB
• find /path -type f -size +1G - Files larger than 1GB
• ls -lhS /path | head -20 - List files sorted by size (largest first)

Disk Information

• cat /proc/partitions - Partition table
• cat /proc/mounts - Mount information
• stat -f /path - Filesystem statistics

Tips

• Always use -h for human-readable sizes
• The du command can be slow on large directories; use --max-depth=1 to limit recursion
• Root filesystem (/) usage above 90% may cause issues