-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 06/24/2012 07:41 PM, Dmitrijs Ledkovs wrote: >> There is already an ext4-specific (depends on creation with -O extent) >> e4defrag >> tool in e2fsprogs since 1.42~WIP-2011-07-02-1. Is there a reason you would >> use >> one tool over the other? >> > > The obvious, you would use e2defrag for ext2, ext3 & ext4 without extents. > > But the question which one to prefer for ext4 with extents still stands.
I have yet to try e4defrag, but my understanding is that it essentially works like most of the other available defrag programs such as shake: it finds fragmented files, and copies them, hoping that when the copy is written, the kernel allocator will manage to make the new copy contiguous. It therefore does nothing for free space fragmentation or keeping similar files in a similar location on disk. e2defrag also has a feature where you can specify particular inodes be given priority over others. This allows you to take files that are needed during boot, and pack them all together at the start of the disk so they can be read rapidly by ureadahead, which gives significant boot time improvement. Due to the ability to perform online defrag, and safety in the face of a crash, I imagine that many users will prefer e4defrag. I hope that having e2defrag still alive and working will provide a good comparison and spur on improvement in e4defrag. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJP573bAAoJEJrBOlT6nu75KUMH/ROIvbrOhSR0FVq29/i69bmy z2nKBevfXRTHA2TLb4LvsnVxa7UMUgSpJpwIhpQreH0FCTBFw7CfpkAiq7yjbbnx Qs1Ad1WLUe3Wzjh/N9HWn5yqPxRhwi8s3RrHTBokhD2RBbZt7Xc04dyRJ+wDJ19/ koB9X+/Ngzfuuhlvnt8o5DCxK6NfObbKRKD+wyPFfYSG/6rzW6B+VQC3VF/DRNTM R+AGv4lp69D6N+6cJohUx2zOsR4EcWWm74pLqpQ7shZqFOgadyyiTdNdyoED/2Uh 0OawawwJVeLp8AjYDdB35nbObKNNe89oftSjWn1KK+gcIV5AwsEn4tibFZe7ZfY= =HF93 -----END PGP SIGNATURE----- -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
