Introduction
(Check Size of Directory in Linux) The Linux operating system represents a powerful system which serves as the foundation for server usage alongside its roles in application development and desktop applications. Linux administration requires checking as well as managing disk space as a fundamental task. Directory size checks help organizations to avoid storage space shortages along with creating effective folder structures.
This article presents multiple ways to determine directory sizes through Linux command-line commands. The guide presents information about the du command in addition to ls, ncdu, and supplementary helpful techniques.
Using the du Command
The du (disk usage) command is the most commonly used tool to check the size of a directory in Linux. It provides information on disk usage by files and directories.
Basic Usage
To check the size of a directory, use the following command:
Explanation of options:
-s: Summarizes the total size of the directory.
-h: Displays the size in a human-readable format (e.g., KB, MB, GB).
Example:
This output indicates that the Documents directory is using 2.5GB of disk space.
Check Size of Subdirectories
To see the size of all subdirectories within a directory, run:
Example output:
This breakdown shows the size of individual subdirectories within Documents.
Sorting Results by Size
To display directory sizes in descending order, use:
This command helps identify which subdirectories are consuming the most space.
Using the ls Command
Although ls is primarily used to list files and directories, it can also be used to check file sizes.
List Files with Sizes
This command displays files along with their sizes in a human-readable format.
However, ls does not show the cumulative size of a directory. It only displays individual file sizes.
Using ncdu for an Interactive View
ncdu (NCurses Disk Usage) is a powerful tool that provides a visual, interactive way to analyze disk usage.
Install ncd
u
On Debian/Ubuntu:
On CentOS/RHEL:
On Arch Linux:
Using ncdu
To check a directory’s size, run:
This launches an interactive interface where you can navigate through directories and analyze disk usage effectively.
Using df to Check Disk Space Usage
While df (disk filesystem) does not check directory sizes, it provides an overview of total disk space usage.
Example output:
This command helps determine overall disk space usage on different partitions.
Using find to Identify Large Files
If a directory contains large files, use find to locate them:
This command finds files larger than 100MB and lists their details.
Using du with grep for Filtering
To filter results for specific file types, use grep:
This command helps locate large log files consuming disk space.
Automating Disk Usage Checks
To automate checking directory sizes, create a cron job:
Add the following line to run du every day at midnight and log results:
This ensures regular monitoring of disk usage.
Finding and Removing Unused Files
To identify and delete unused files, use:
This removes files not accessed in the last 30 days.
Checking Available Inodes
Inodes store metadata about files. If a system runs out of inodes, new files cannot be created even if disk space is available.
To check inode usage, use:
Example output:
If the IUse% value is close to 100%, you may need to delete unnecessary small files to free up inodes.
Conclusion
Linux users must practice directory size checks as an important step in their disk space management strategy. The main tool for checking disk usage is du but ncdu offers an interactive interface for disk usage analysis. Storage management can be supported using a combination of df, ls and find tools.
By establishing automatic disk usage checks combined with routine old file deletion the system can operate at its optimal level. Using these commands enables users to achieve optimization of their system storage through effective monitoring processes.
