FILEFRAG(8) System Manager's Manual FILEFRAG(8)
NAME
filefrag - report on file fragmentation
SYNOPSIS
filefrag [ -bblocksize ] [ -BeEkPsvVxX ] [ files... ]
DESCRIPTION
filefrag reports on how badly fragmented a particular file might be. It
makes allowances for indirect blocks for ext2 and ext3 file systems, but
can be used on files for any file system.
The filefrag program initially attempts to get the extent information
using FIEMAP ioctl which is more efficient and faster. If FIEMAP is not
supported then filefrag will fall back to using FIBMAP.
OPTIONS
-B Force the use of the older FIBMAP ioctl instead of the FIEMAP
ioctl for testing purposes.
-bblocksize
Use blocksize in bytes, or with [KMG] suffix, up to 1GB for out-
put instead of the file system blocksize. For compatibility with
earlier versions of filefrag, if blocksize is unspecified it de-
faults to 1024 bytes. Since blocksize is an optional argument,
it must be added without any space after -b.
-e Print output in extent format, even for block-mapped files.
-E Display the contents of ext4's extent status cache. This feature
is not supported on all kernels, and is only supported on ext4
file systems.
-k Use 1024-byte blocksize for output (identical to '-b1024').
-P Pre-load the ext4 extent status cache for the file. This is not
supported on all kernels, and is only supported on ext4 file sys-
tems.
-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 that are understood by the current
version.
-x Display mapping of extended attributes.
-X Display extent block numbers in hexadecimal format.
AUTHOR
filefrag was written by Theodore Ts'o <tytso@mit.edu>.
E2fsprogs version 1.47.2 January 2025 FILEFRAG(8)
Generated by dwww version 1.16 on Tue Dec 16 06:42:03 CET 2025.