filefrag

report on file fragmentation

TLDR

Display fragmentation report for files

$ filefrag [path/to/file1] [path/to/file2]

Report using 1024 byte blocksize

$ filefrag -k [path/to/file]

Report using specific blocksize

$ filefrag -b[1024|1K|1M|1G] [path/to/file]

Sync file before requesting mapping

$ filefrag -s [path/to/file1] [path/to/file2]

Display verbose report with extent details

$ filefrag -v [path/to/file1] [path/to/file2]

Display mapping of extended attributes

$ filefrag -x [path/to/file1] [path/to/file2]

Display extent block numbers in hexadecimal

$ filefrag -X [path/to/file]

Print version number

$ filefrag -V

SYNOPSIS

filefrag [-b blocksize] [-BeEkPsvVxX] [files...]

filefrag reports on how badly fragmented a particular file might be. It shows the number of extents (contiguous blocks) for each file, which indicates fragmentation level. A file with 1 extent is not fragmented; more extents indicate higher fragmentation.Useful for identifying files that may benefit from defragmentation.

PARAMETERS

-b blocksize

Use blocksize in bytes, or with [KMG] suffix, up to 1GB for output instead of the filesystem blocksize. If blocksize is unspecified it defaults to 1024 bytes. Must be added without any space after -b.

-B

Force use of the older FIBMAP ioctl instead of the FIEMAP ioctl for testing purposes.

-e

Print output in extent format, even for block-mapped files.

-E

Display the contents of ext4's extent status cache. Only supported on ext4 filesystems.

-k

Use 1024-byte blocksize for output (identical to '-b1024').

-P

Pre-load the ext4 extent status cache for the file. Only supported on ext4 filesystems.

-s

Sync the file before requesting the mapping.

-v

Be verbose when checking for file fragmentation.

-V

Print version number of program and library. If given twice, also print the FIEMAP flags understood by the current version.

-x

Display mapping of extended attributes.

-X

Display extent block numbers in hexadecimal format.

CAVEATS

Part of e2fsprogs. Works best on ext2/ext3/ext4 but supports other filesystems via FIEMAP ioctl. The -E and -P options are ext4-specific and not supported on all kernels.