On 28/03/2016 11:01, The Natural Philosopher wrote:
On 28/03/16 06:00, Johnny B Good wrote:
On Sat, 26 Mar 2016 09:28:35 +0000, The Natural Philosopher wrote:

On 25/03/16 21:20, Vir Campestris wrote:
On 24/03/2016 22:43, The Natural Philosopher wrote:
Oh the joys of Linux, and no de fragging ever unless the disk is 100%
full

I've heard this said, and I never can work out how.

If I put 5000 files on my disk, and delete every alternate one, how can
it not be fragmented?

Well of course it is somewhat, but the point is that new files tend to
be written in the middle of the biggest free space, depending on the
actual disk format in use, so they tend to simply grow linearly.

Fragmentation isn't a file in a random place, its a file in dozens of
random places, so to get the entire contents takes many seeks.

http://www.howtogeek.com/115229/htg-...x-doesnt-need-
defragmenting/

I was quite surprised at the explanation. The strategy of scattering
files across the disk volume 'in order to allow them space into which to
grow' seemed so bogus, seeing as how most files are edited by writing a
complete new copy before renaming the original as a backup file, either
temporarily simply to avoid the naming conflict or as a safety rollback
copy.


Where are you going to put that new file then? Into all the tiny little
gaps left by previous deleted ones, as none of the spaces were big
enough to hold new bigger files?

If you delete a single file bang in the middlke of a huge gap you get
the huge gap back, with no clutter.

skip intersting design of tape FAT

With my strategy of minimising fragmentation of free space being *such*
a "No Brainer", I've always assumed MSFT's FAT based FSes used a similar
strategy, BICBW.


The words in that paragraph are in te wro9ng order.

I've always assumed MSFTs FAT based FSes were the result of no brain no
strategy.

FAT was basically just a formalisation of what was inherited from
CP/M... it was not until MS hired a patent lawyer with the intention of
finding new way to monetise old intellectual property, that FAT was even
really acknowledged as being an item rather than just a bit of
technology that loads of people used. It main goal was simplicity and
lightweight implementation - as was demanded by the needs of the time.



--
Cheers,

John.

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