Defrag-Compress disk to save space problems

[Guest]

Hi all,
I compressed my c drive to save space, and now I am
trying to defrag. IT says I have 20 % free space. The disk
is VERY fragmented. Everytime I run defrag, it runs for a minute,
and then reports that it can't defrag some files.

I have a beautiful E drive with TONS of space on it.
So... did the compressing screw up the ability for me
to defrag? If so, any way I can un-compress the disk?!!
THanks for your help!!
Ro
(e-mail address removed)

 

[JS]

First Uncompressing the files will only eat up more space on the C: drive
leaving you will little or no free space, which you do not want as you need
more space not less!

You can free up space on your C: drive by moving:
Changing the Default Location of the My Documents Folder (to your E: drive)
See: http://support.microsoft.com/kb/310147
Also:
http://www.techsupportalert.com/how_to_move_my_documents.htm

You can also free up disk space on the C: drive by running XP's 'Disk
Cleanup Tool'
(Start/All Programs/Accessories/System Tools/Disk Cleanup)

To for move files that can be removed take a look at CCleaner:
You can use this tool to remove Internet history info, cookies, temp files,
auto complete and other junk. In the 'Windows' tab listing check the item
types you want deleted.
CCleaner also provides/has available customization, see Options/Custom to
add any other/additional folders you want files deleted from.
http://www.ccleaner.com/

JS

 

[crazyal]

compressing files will slow down your computer

 

[Guest]

THanks JS and Craz..
I wish I could uncompress my files on my E drive!
ANd, I'll take a look at all of the advise you gave JS.
Looks like some good space saving tips!

 

[Ken Blake, MVP]

compressing files will slow down your computer

Not necessarily.

True, it takes time to uncompress and recompress the files every time
you read and write them. On the other hand, compressed files are
smaller than uncompressed files and take less time to read and write.

Which factor is more significant depends on the relative speeds of
your processor and hard drive, but on most modern computers, the
result is a near wash, and you shouldn't see a significant difference
either way.

 

[JS]

Let us know what your results are.

JS

THanks JS and Craz..
I wish I could uncompress my files on my E drive!
ANd, I'll take a look at all of the advise you gave JS.
Looks like some good space saving tips!

 

[John John]

Not necessarily.

True, it takes time to uncompress and recompress the files every time
you read and write them. On the other hand, compressed files are
smaller than uncompressed files and take less time to read and write.

Hmmm. They don't take less time to read and write, Ken, they are read
and written to in the "uncompressed" state. To read or write to the
files, the operating system must first decompress the files and then
recompress them when you close them, it isn't actually reading or
writing to the smaller compressed file. To work with compressed files
the operating system must do additional work not otherwise needed with
uncompressed files.

John

 

[Ken Blake, MVP]

Hmmm. They don't take less time to read and write, Ken, they are read
and written to in the "uncompressed" state. To read or write to the
files, the operating system must first decompress the files and then
recompress them when you close them, it isn't actually reading or
writing to the smaller compressed file.

What you say makes no sense at all. If you write a compressed file in
an uncompressed state, the entire point of compression goes away. The
whole point of compression is to write the files in their compressed
state, so they take up less space on the drive.

 

[John John]

What you say makes no sense at all. If you write a compressed file in
an uncompressed state, the entire point of compression goes away. The
whole point of compression is to write the files in their compressed
state, so they take up less space on the drive.

That is not how it works, Ken. The operating system does not directly
read or write to compressed files, the files are decompressed and
recompressed every time you access them, this is done by the operating
system without user intervention. The whole point of compression does
not go away because of this fact, you either compress seldom used files
to save space or you can compress almost all the files on your computer
to save space, that they are decompressed if you access them will not
defeat the purpose of compression because you will not open all the
files at the same time. Working with compressed files means that the
processor will be doing extra work every time that you open or close,
move or copy, access or send them over a network, they must first be
decompressed, they are only compressed when they are not in use.

http://support.microsoft.com/kb/307987
http://support.microsoft.com/kb/251186/EN-US/

John

 

[Ken Blake, MVP]

That is not how it works, Ken. The operating system does not directly
read or write to compressed files, the files are decompressed and
recompressed every time you access them, this is done by the operating
system without user intervention.

Yes, of course. I didn't say otherwise. But when the file is on the
disk drive, it is compressed--that's how space is saved. When you
write the file to disk, you are writing a compressed file, and when
you read the file again, you are reading a compressed file (the
compression and uncompression take place transparently, as you say).
The point is that the physical I/O takes place with the files in their
compressed state, and those files are smaller than if they were not
compressed. Because they are smaller, it takes less time to read or
write them.

The whole point of compression does
not go away because of this fact, you either compress seldom used files
to save space or you can compress almost all the files on your computer
to save space, that they are decompressed if you access them will not
defeat the purpose of compression because you will not open all the
files at the same time.


Working with compressed files means that the
processor will be doing extra work

Yes, I said that in my original message in this thread. It takes extra
processor time to compress and uncompress. But I also pointed out that
you also *save* time every time you write or read the file, because
(as I said above) you are writing or reading fewer bytes.

So using compression costs time on the one hand (extra CPU time to
compress and uncompress) and saves time on the other hand (less hard
drive I/O time because you are reading or writing fewer bytes). In
most cases, it comes out to a near wash.

 

[WaIIy]

Hi all,
I compressed my c drive to save space, and now I am
trying to defrag. IT says I have 20 % free space. The disk
is VERY fragmented. Everytime I run defrag, it runs for a minute,
and then reports that it can't defrag some files.

I have a beautiful E drive with TONS of space on it.
So... did the compressing screw up the ability for me
to defrag? If so, any way I can un-compress the disk?!!
THanks for your help!!
Ro
(e-mail address removed)

Try installing programs on your E drive and take them off C