How do I find file fragmentation for specific file under Linux?

File fragmentation occurs when a file is stored on a disk in multiple non-contiguous blocks, rather than as a single contiguous block. File fragmentation can affect the performance of the disk, as the disk drive may need to seek and read multiple blocks to access the file.

To find file fragmentation for a specific file in Linux, you can use the "filefrag" utility. "filefrag" is a command-line tool that displays information about the fragmentation of a file on a Linux file system.

To find file fragmentation for a specific file in Linux, follow these steps:

1. Install the "e2fsprogs" package on your Linux system. "filefrag" is part of the "e2fsprogs" package, which provides utilities for manipulating ext2/ext3/ext4 file systems. You can use the "apt-get" or "yum" command to install the "e2fsprogs" package if it is not already installed.

2. Open a terminal and navigate to the directory where the file is located.

3. Use the "filefrag" command to display information about the fragmentation of the file. For example:

filefrag FILE

Replace "FILE" with the name of the file that you want to check for fragmentation.

4. "filefrag" will display information about the fragmentation of the file, including the number of extents (contiguous blocks) that the file is stored in, the extent size, and the physical block numbers of the extents. For example:

filefrag: FILE: 3 extents found

This output indicates that the file is stored in 3 extents.

With these steps, you should be able to find file fragmentation for a specific file in Linux using the "filefrag" utility.

Note: File fragmentation can be reduced by defragmenting the file system or by using a file system that supports extents and dynamic allocation, such as ext4. Consult the "filefrag" and "e2fsprogs" documentation for more information on the available options and usage.