du

Estimate file and directory space usage.

Synopsis

du [options] [path]

When to Use It

Use du when a server or local workspace is running out of disk, when a build artifact suddenly becomes huge, or when you need a quick directory-by-directory breakdown before cleaning up logs, caches, containers, or uploads.

Core Options

-h

Human-readable sizes.

-s

Summary only.

--max-depth N

Limit recursion depth.

-a

Show files as well as directories.

-x

Stay on one filesystem.

Usage Examples

Directory Summary

Total size of a folder.

du -sh ./logs

Top-level Breakdown

Sizes of immediate subfolders.

du -h --max-depth=1 ./

Include Files

Show file sizes too.

du -ah ./data | sort -h | tail

Apparent Size

Inspect apparent size instead of allocated blocks.

du -sh --apparent-size ./backup.tar

Single Filesystem

Avoid crossing into mounted volumes.

du -xh --max-depth=1 /var

Common Mistakes

  • du reports allocated disk usage, not always the exact apparent file size, so sparse files can look smaller or larger than expected.
  • Running du without depth limits on a very large tree can be slow and noisy; add -s or --max-depth when you only need summaries.
  • If you forget -x, the command may cross filesystem boundaries and mix results from mounted volumes.

Related

df Command Guide

Check free space per filesystem after using du to find the heavy directories.

find Command Guide

Locate oversized files or old artifacts after identifying the problem directory.

lsof Command Guide

Debug cases where disk space is still missing because deleted files remain open.

Built for builders.