8

This is an output from dumpe2fs:

root: ~/# dumpe2fs -h /dev/sdb3 | grep -i 'fragment|block size'
dumpe2fs 1.39 (29-May-2006)
Block size:               4096
Fragment size:            4096
Fragments per group:      32768

Is this related to disk fragmentation?

12

No. ext3fs doesn't support block fragmentation so a one byte file will use a whole 4096 block.

On the opposite, for example UFS supports four fragments in a block so small files won't fill a file system as fast as they will do on ext3fs.

This is unrelated to disk fragmentation which is about file data blocks not being contiguous and sequential.

| improve this answer | |
  • 1
    Thanks for the answer. The mkfs manual is very cryptic-only a one liner for the "-f fragment-size" option. If block fragmentation is not supported in ext2/3/4, why does the -f option appear in the mke2fs manual? Nothing serious, just curious. – JBraganza Jul 9 '11 at 0:50
  • 3
    Just in case someone want to implement it. See the BUGS section in the very same manual page: mke2fs accepts the -f option but currently ignores it because the second extended file system does not support fragments yet. – jlliagre Jul 9 '11 at 1:27
  • It is one of those things that was put in as a planned feature, but never implemented. – psusi Jul 9 '11 at 1:28
  • @psusi: actually, it's one of those things that was put to make ext2fs more like UFS and FFS. Probably noone ever expected it to be implemented in the future. – ninjalj Jul 10 '11 at 20:38
  • At least the manual page writer expected it to be implemented. – jlliagre Jul 10 '11 at 21:51

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.