Char Jackson wrote:
On 4 Nov 2018 15:02:31 GMT, Frank Slootweg
wrote:

"J. P. Gilliver (John)" wrote:
In message , Pamela
writes:
On 18:49 30 Oct 2018, Char Jackson wrote in
news []
Defragging doesn't reclaim space.

Wouldn't a defrag reclaim slack space hidden in cluster tips?
[]
AFAIK, a fragmented file fills all the clusters it uses except the last
one, just the same as an unfragmented one.

What - I think - Pamela is hinting at, is that defragmentation can
combine the used contents of several partially filled clusters into one
or more clusters, thereby potentially freeing up clusters and hence
"reclaim space".

When files are stored on disk, the only partial clusters are each file's
final cluster, so of course you can't combine those.

Yeah, apparently I was confusing things with another - than NTFS -
filesystem, where multiple small files or small final parts of files can
be stored in one 'cluster'.

That probably was HP's HFS filesystem (an implementation of the
Berkeley Fast File System for UNIX), which has blocks and fragments,
where multiple fragments (f.e. 8, 1KB fragments) make up one (f.e. 8KB)
block and each fragment can contain part of a file or a small file.

Sigh! And then to think that (UNIX) filesystems was one of my
specialities! :-( Well, it has been 15 years, so I'm probably allowed to
'forget' some things.

[...]

Bottom line, if someone is trying to free up disk space, the defragger
is the wrong tool for the job.

Unless, you're use a Real File System (TM)! :-)