Detailed explanation of du command under Linux

The du command under Linux is a powerful tool for disk space usage statistics and troubleshooting.

Introduction:
In Linux systems, rational utilization and troubleshooting of disk space is one of the key tasks. In order to help us understand the disk space occupied by files and directories, and troubleshoot the problem of excessive space usage, we can use the du command. This blog will introduce in detail the past and present, functions, usage and application scenarios of the du command in an easy-to-understand manner, helping readers to fully understand the du command and master its application in disk management and troubleshooting.

1. The past and present life of du instruction

In early Unix systems, the du (disk usage) command was used to count the disk space occupied by directories or files. With the development of operating systems, the du command has been further improved and expanded, and has become an important tool for disk space usage statistics in Linux systems. It can provide detailed information about the disk space usage of files and directories, helping us understand the distribution and occupation of disk space.

2. Function and usage of du command

The du command is mainly used to count the disk space occupied by files and directories. The following are common uses of the du instruction:

1. Count the disk space usage of a specified directory:

du [目录路径]

This command will count the disk space occupied by files in the specified directory and its subdirectories, and display the results in bytes.

2. Displayed in human-readable format:

du -h [目录路径]

This command will display disk space usage in a human-readable format, converting the used capacity into easy-to-understand units (such as GB, MB).

3. Show disk space usage for all files and directories:

du -a [目录路径]

This command will count the disk space occupied by all files and directories in the specified directory and its subdirectories.

4. Only counts the disk space usage of directories, excluding subdirectories:

du -S [目录路径]

This command will count the disk space occupied by files and directories in the specified directory, but does not include subdirectories.

5. Exclude disk space statistics for specified directories or files:

du --exclude=[目录/文件路径] [目录路径]

This command will exclude the specified directory or file from counting disk space usage.

3. Application scenarios of du command

1. Disk space management:
   Use the du command to quickly understand the disk space occupied by files and directories and help us manage disk space. By looking at disk space usage, we can determine which files or directories are taking up a lot of space and take necessary steps to clean or move them.

2. Troubleshooting the problem of high space usage:
   When the disk space usage is too high, we can use the du command to troubleshoot the problem. By counting the disk space usage of each file and directory, we can determine which files or directories are taking up a lot of space, and then analyze their contents in depth to find out why the space usage is too high.

3. Combine with other commands for deeper analysis:
   The du command can be used in conjunction with other commands for deeper disk space analysis. For example, we can use the du command together with the sort command to sort files and directories according to disk space size to find the files or directories that occupy the largest space.

4. Example of du command

Here are some common examples of du instructions:

1. Display the disk space usage of a specified directory:

du /home

2. Display disk space usage in human-readable format:

du -h /var/log

3. Show disk space usage for all files and directories:

du -a /etc

4. Only counts the disk space usage of directories, excluding subdirectories:

du -S /usr

5. Learn more about the du command

If you want to learn more about the functions and usage of the du instruction, you can refer to the following reference links:

• Official documentation for the du command
• Detailed explanation of Linux du command

Through the reference link, we can further learn and understand more features and usage of the du command, as well as more applications in disk management and troubleshooting.

Conclusion:
This blog introduces the du command under Linux in detail, including its past and present, functions, usage and application scenarios. As a powerful tool for disk space usage statistics and troubleshooting, the du command helps us effectively manage and monitor the disk space usage of the file system. Through the du command, we can quickly understand the disk space usage of files and directories, promptly discover the problem of excessive space usage, and take corresponding measures.

Perform processing. At the same time, we also provide examples and reference links for a deeper understanding and application of du instructions.

Reference links:

• Official documentation for the du command
• Detailed explanation of Linux du command