Re: XD picture card reformatting?

"David J Taylor" wrote:
Jürgen Exner wrote:
Some people believe in 'preventive maintenance', but there is really
no solid base for that, either. Also, while formatting does eliminate
file fragmentation (which is not a significant problem on flash
memory in the first place) so will simply deleting the files, too.

Deleting files does not prevent fragmentation, it increases the likelihood
of fragmentation happening, as the data area used by a file is not
immediately freed (only the directory entry is marked "erased"),

and also those sectors that were used by that file are returned to the
pool of free sectors. They are not physically overwritten or flashed,
but the sectors can and will be used any time a new file is to be saved.

and the
free area has an increasing number of fragments.

Only if there are sectors left from files that have not been deleted.

On older cameras, fragmentation /can/ be an issue and resulting in a
slower writing speed, but I haven't seen this on cameras made in the last
5-6 years.

Possible, I guess. But opposite to hard drives there are no physical
parts on a flash card that need to be moved to a different part of the
drive. Therefore the delay _should_ be very minimal if there is any at
all.

Less fragmentation makes for easier file recovery after an
accident,

That is very true. Therefore it is not a good idea to make a habit of
deleting only some files and keep others because that will lead to
fragmentation, especially on those FAT file systems that are used for
camera flash memory.

jue
.

Relevant Pages

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