puzzled about files on disk

[sobriquet]

Hi.
Something baffles me. Perhaps someone here can explain it.

If I go to the properties of my C drive on my laptop, the size
reported is smaller than the total size of the files and folders on
drive C:
http://img200.imageshack.us/img200/2843/dataa.jpg

How can the size of all selected files and folders on the C drive
exceed the total capacity of that same C drive?

Greetings and thanks in advance for any explanations, Niek

 

[mscotgrove]

Hi.
Something baffles me. Perhaps someone here can explain it.

If I go to the properties of my C drive on my laptop, the size
reported is smaller than the total size of the files and folders on
drive C:http://img200.imageshack.us/img200/2843/dataa.jpg

How can the size of all selected files and folders on the C drive
exceed the total capacity of that same C drive?

Greetings and thanks in advance for any explanations, Niek

Do you have NTFS compression enabled forall or some of the files?

Michael
www.cnwrecovery.com

 

[sobriquet]

Do you have NTFS compression enabled forall or some of the files?

Michaelwww.cnwrecovery.com

Not that I know of. In the main properties for the drive, I don't have
the box checked for compressing files on that volume to save space.

 

[mscotgrove]

Not that I know of. In the main properties for the drive, I don't have
the box checked for compressing files on that volume to save space.- Hidequoted text -

- Show quoted text -

Try a chkdsk and see if the results stay the same.

Michael

 

[Arno]

Hi.
Something baffles me. Perhaps someone here can explain it.

If I go to the properties of my C drive on my laptop, the size
reported is smaller than the total size of the files and folders on
drive C:
http://img200.imageshack.us/img200/2843/dataa.jpg

How can the size of all selected files and folders on the C drive
exceed the total capacity of that same C drive?

Greetings and thanks in advance for any explanations, Niek

Probaly sparse files. NTFS does now write blocks that are filled
with zeros.

Arno

 

[sobriquet]

Probaly sparse files. NTFS does now write blocks that are filled
with zeros.

Arno

But surely, if there had been previous data on disk that has been
deleted, it would have to write blocks of zeros if a file contains
nothing but zeros, otherwise the file would contain data from files
that had been stored on that block previously?

 

[Arno]

But surely, if there had been previous data on disk that has been
deleted, it would have to write blocks of zeros if a file contains
nothing but zeros, otherwise the file would contain data from files
that had been stored on that block previously?

No. It does not even allocated blocks that would contain all zeros.
This is done by the block-to-file mapping mechansism.

A sparse file only gets blocks allocated for the parts that contain
actual data.

Arno

 

[sobriquet]

No. It does not even allocated blocks that would contain all zeros.
This is done by the block-to-file mapping mechansism.

A sparse file only gets blocks allocated for the parts that contain
actual data.

Arno

Ah ok.. but only on NTFS, or on FAT16/32 as well?

 

[David Brown]

Ah ok.. but only on NTFS, or on FAT16/32 as well?

Only NTFS (on Windows - lots of file systems on *nix support sparse
files too).

 

[Arno]

Only NTFS (on Windows - lots of file systems on *nix support sparse
files too).

The mechanism may be a bit different: On *nix, a spares file
has blocks unallocated that were not written. These return zeros
on reading, but if you write zeros they get allocated. (Found
that out the hard way....) If I understand this correctly,
NTFS does not allocate blocks if you write all zeros to an aera.

Arno

 

[John Turco]

The mechanism may be a bit different: On *nix, a spares file
has blocks unallocated that were not written. These return zeros
on reading, but if you write zeros they get allocated. (Found
that out the hard way....) If I understand this correctly,
NTFS does not allocate blocks if you write all zeros to an aera.

Arno

Minor correction...the plural of "zero" is:

zeroes

 

[Arno]

Minor correction...the plural of "zero" is:

Marie's Musings <http://fairiesandtails.blogspot.com>

There is only one zero in the universe, so it has no plural!

Proof:

Let 0a and 0b both be arbitrary zeros.

Conjecture: Assume they are different.

Then 0a != 0b. But 0a + 0b = 0a (because 0b is a zero)
and 0a + 0b = 0b (because 0a is a zero) and hence 0a = 0b
by transitivity of '='. Buit this is contradiction to
0a != 0b and hence the conjecture is wrong. This means
0a = 0b. We conlcudlde that they are all equal and hence
there is only one!

q.e.d.

So you can use the same one zero multiple times, but it
stays the same! So the correct usage would be "... if you
write all zero ... " ;-)=)

Arno

 

[John Turco]

There is only one zero in the universe, so it has no plural!

Proof:

Let 0a and 0b both be arbitrary zeros.

Conjecture: Assume they are different.

Then 0a != 0b. But 0a + 0b = 0a (because 0b is a zero)
and 0a + 0b = 0b (because 0a is a zero) and hence 0a = 0b
by transitivity of '='. Buit this is contradiction to
0a != 0b and hence the conjecture is wrong. This means
0a = 0b. We conlcudlde that they are all equal and hence
there is only one!

q.e.d.

So you can use the same one zero multiple times, but it
stays the same! So the correct usage would be "... if you
write all zero ... " ;-)=)

Arno

That's some rather convoluted "logic" you have, there (all
kidding aside).

 

[Arno]

<heavily edited for brevity>

That's some rather convoluted "logic" you have, there (all
kidding aside).

It is the accepted proof for this fact. Seriously.

Arno

 

[Arno]

It is certainly the clearest proof I know of, and generalises to all
groups. Mind you, the term "conlcudlde" is new to me

I think that may be due to alcohol being used in the production
of the proof. I recreated it from memory.

My favourite proof about zero is the "cheese sandwich theorem" :

1. Nothing is better than complete happiness.
2. A cheese sandwich is better than nothing.
3. Therefore, a cheese sandwich is better than complete happiness.

Nice!

Arno

 

[John Turco]

It is certainly the clearest proof I know of, and generalises to
all groups. Mind you, the term "conlcudlde" is new to me

My favourite proof about zero is the "cheese sandwich theorem" :

1. Nothing is better than complete happiness.
2. A cheese sandwich is better than nothing.
3. Therefore, a cheese sandwich is better than complete happiness.

4. What in hell, are you and Arno, even >discussing<?

 

[Arno]

4. What in hell, are you and Arno, even >discussing<?

Mathematics and language. Fun!

Arno

 

[John Turco]

I thought my "cheese sandwich theorem" was perfectly clear...

Either you are the sort of person that likes such jokes, or you
are not. If you /do/ like them, I can give you a proof that
everyone on the Internet has the same type of computer.

I'm not that "sort of person," obviously.

 

[John Turco]

Mathematics and language. Fun!

Negative, with respect to math! It was my poorest subject, in school.

Even arithmetic, itself, still causes me some trouble (i.e., long
division).

 

[another someone]

Something baffles me. Perhaps someone here can explain it.

If I go to the properties of my C drive on my laptop, the size
reported is smaller than the total size of the files and folders on
drive C:
http://img200.imageshack.us/img200/2843/dataa.jpg

How can the size of all selected files and folders on the C drive
exceed the total capacity of that same C drive?

Greetings and thanks in advance for any explanations, Niek

Very old thread, but I see that no one answered it, so I will.

If you were to dump a list of all the files in the Windows folder into a
spreadsheet or database and sort by filename, you'd see that many files
appear to exist in multiple locations...EXCEPT that in reality there is only
a single copy of those files and the 'additional copies' are only links that
point to the actual copy. Windows keeps track of the links, so that if you
issue a delete command against a file that has those kinds of links, one of
the links is simply destroyed and the original (only actual copy) is
preserved.

This is the same way that Microsoft was appearing to put ~2GB+ of files on a
700MB CD back in the day.