"Brash, Matthew" wrote:
> Supposedly defragging is unnessecary in Linux. The Ext2 file system doesn't
> get fragmented or something. Can anyone confirm/trash this idea?
>
>
Confirm.
The ext2 filesystem is, in the sense of the FAT-type filesystems fragmented a
small amount--and it remains at that amount and does its "defragging" largely
on the fly.
The FAT system defrag makes files contiguous (occupying successive sectors on
disk) and stacks them end-to-end from the beginning of the data area on the
disk. When a file is removed, its allocated blocks are returned to the pool of
unallocated blocks and used whenever.
FAT32 is slightly more efficient in access and LESS efficient on space because
it does not handle a 5K file, for example, with any grace at all. But the
efficiency in access, which is slight to begin with, becomes terrible as soon
as some files change size or some are deleted and others added. Thus we have
the defrag. Note that Microsoft does not offer a defragmenter for NTFS... It
is supposedly a more efficient system but who knows since they don't pass out
the specifications....
So ext2fs doesn't really need a defragmenter. It is not bound to jamming
everything as near as possible to the beginning of the disk to get effciency
and most files have their data blocks stacked end-to-end though there will be a
sort of checkerboard effect on what is used versus what is free across the disk
or disk partition.
Windows is based on a close link between the physical storage on the disk and
the logical storage there. ext2fs is at a higher level of abstraction,
deliberately fragmenting the free space on the disk so files are generally
unfragmented.. Recent improvements have made ext2fs even better. rpmfind.net
reports success with the journaling ext3 fs, and you can see the Reiserfs is
now offered in linux-mandrake. None of those filesystems really need
defragmenters.
Civileme
