FILEFRAG(8)

📦
version 1.47.4 · 6 versions
, in alpine 3.24, arch rolling, nixpkgs unstable, ubuntu stonking

💖 FILEFRAG(8) 💖

okay bestie, welcome to filefrag — a lil' tool from the System Manager's Manual section 8 (that's the sysadmin zone, we love her) 🎀

✨ NAME ✨

filefrag — the girl who reports on file fragmentation 💅

🌸 SYNOPSIS 🌸

filefrag [ -bblocksize ] [ -BeEkPsvVxX ] [ files... ]

🦋 DESCRIPTION 🦋

So basically, filefrag spills the tea on how badly fragmented a particular file might be. It's giving investigative journalism but for your disk 🕵️♀️✨

It makes allowances for indirect blocks for ext2 and ext3 file systems — cute of it — but fr fr it can be used on files for any file system. No gatekeeping here 💖

The filefrag program initially attempts to get the extent information using FIEMAP ioctl, which is more efficient and faster (main character energy, no cap). And if FIEMAP is not supported? Bestie, it doesn't panic — it falls back to using FIBMAP. Lowkey resilient 💪

💅 OPTIONS 💅

  • -B — Force the use of the older FIBMAP ioctl instead of the FIEMAP ioctl, for testing purposes. Retro era activated 🕰️
  • -bblocksize — Use blocksize in bytes, or with [KMG] suffix, up to 1GB, for output instead of the file system blocksize. For compatibility with earlier versions of filefrag, if blocksize is unspecified it defaults to 1024 bytes. And hear me out: since blocksize is an optional argument, it must be added without any space after -b. No space. Zero. Not even one. She's sensitive about it 😭
  • -e — Print output in extent format, even for block-mapped files. Extent format era, periodt ✨
  • -E — Display the contents of ext4's extent status cache. Heads up though: this feature is not supported on all kernels, and it is only supported on ext4 file systems. So check before you get attached 🙈
  • -k — Use 1024-byte blocksize for output (identical to '-b1024'). Same vibe, shorter name 🎀
  • -P — Pre-load the ext4 extent status cache for the file. Same disclaimer as before, bestie: not supported on all kernels, and only supported on ext4 file systems 💀
  • -s — Sync the file before requesting the mapping. Get it together first, then ask 💫
  • -v — Be verbose when checking for file fragmentation. She's a talker and honestly? We stan 🗣️
  • -V — Print version number of program and library. And if you give it twice, it also prints the FIEMAP flags that are understood by the current version. Double tap for extra lore 👑✨
  • -x — Display mapping of extended attributes. xattrs, but make it visible 🌈
  • -X — Display extent block numbers in hexadecimal format. Hex girlies rise up 🔥

🫶 AUTHOR 🫶

filefrag was written by Theodore Ts'o <tytso@mit.edu>. Shoutout to the icon who built her 💖

ngl bestie, if you're checking fragmentation on an ext4 box and -E or -P just quietly doesn't work? That's the kernel talking, not you. It's literally not supported on all kernels. Not your fault, babe 😭

and that's the whole page, bestie!! this one's from E2fsprogs version 1.47.4, dated March 2025 — so it's fresh, it's current, it ate and left no crumbs 🌸✨🦋 mwah, go defrag something (or don't, it's a report tool, love that for us) 💜🎀

📦 where this page comes from