filefrag - Linux

Overview

filefrag is a powerful command-line utility that analyzes file fragmentation on ext2/3/4 file systems. It provides detailed information about the extent and distribution of fragmentation, helping system administrators and users optimize disk performance.

Syntax

filefrag [options] [FILESYSTEM]

Options/Flags

• -v, –verbose: Enable verbose output, displaying additional information.
• -s, –summary: Display only a summary of fragmentation statistics.
• -p, –plot: Generate a histogram plot of fragmentation data.
• -l, –long: Display all file details, including extent information.
• -a, –all: Analyze all files, regardless of size or access time.

Examples

Analyze fragmentation of a specific file system:

filefrag /dev/sda1

Display only a summary of fragmentation statistics:

filefrag -s /dev/sda1

Generate a histogram plot of fragmentation data:

filefrag -p /dev/sda1

Display all file details, including extent information:

filefrag -l /dev/sda1

Common Issues

• Missing filesystem argument: Ensure to specify a valid filesystem path as the first argument.
• Insufficient disk space: The plot option (-p) requires sufficient free disk space.
• Unsupported filesystem: filefrag only supports ext2, ext3, and ext4 filesystems.

Integration

• Combine with find: Identify fragmented files using find -exec filefrag {} \;.
• Create scripts: Automate fragmentation analysis and reporting tasks.
• Use in performance optimization tools: Integrate filefrag into scripts to monitor and troubleshoot file system performance.

Related Commands

• df: Display disk usage statistics.
• fsck: Check and repair file systems.
• e2fsck: Specific file system checker for ext2/3/4 filesystems.