Defragging disk with less than 5% free

[Lars]

If I try and defragg a disk which has less than 5% free then XP's
defragger says:

--------------- QUOTE -------------
Volume 160-DATA (E has only 5% free space available for use by Disk
Defragmenter. To run effectively, Disk Defragmenter requires at
least 15% usable free space. There is not enough disk space to
properly complete the operation. Delete some unneeded files on your
hard disk, and then try again.
--------------- END QUOTE -----------

Then it adds at the end of the above message:
"Do you want to run Disk Defragmenter now anyway?"

Does this mean it is actually ok to defrag with under 5% spare or
will I run the risk of losing data?

 

[Alias]

If I try and defragg a disk which has less than 5% free then XP's
defragger says:

--------------- QUOTE -------------
Volume 160-DATA (E has only 5% free space available for use by Disk
Defragmenter. To run effectively, Disk Defragmenter requires at
least 15% usable free space. There is not enough disk space to
properly complete the operation. Delete some unneeded files on your
hard disk, and then try again.
--------------- END QUOTE -----------

Then it adds at the end of the above message:
"Do you want to run Disk Defragmenter now anyway?"

Does this mean it is actually ok to defrag with under 5% spare or
will I run the risk of losing data?

I think it means it will run improperly and ineffectively. Why don't you
free up some space first instead of taking chances?

 

[dhuva11]

You could run diskcleanup and get rid of unwanted files and free up
some space first and then defragment. Also uninstall any programs you
dont use anymore. Its important to cleanup and defrag regularly for the
system to be fast and stable.

A good third party utility with automatic features might defrag with
lesser free disk space than the built in..also it is a good option for
regular defrag, once set, it will run daily but defrag only when needed.

 

[Greg Hayes/Raxco Software]

Lars,

It won't "hurt" anything if you try to defrag with this low amount of free
space. The worse that will happen is that the built-in defragmenter won't
actually be able to accomplish anything.

- Greg/Raxco Software
Microsoft MVP - Windows File System

Disclaimer: I work for Raxco Software, the maker of PerfectDisk - a
commercial defrag utility, as a systems engineer in the support department.

Want to email me? Delete ntloader.

 

[redwood]

Yes, for an improvement through defrag there shud be enuf free disk
space for the defragger to move the non contiguous chunks together.
its best to defrag before the red gets too much

 

[The Cuddly Curmudgeon]

If I try and defragg a disk which has less than 5% free then XP's
defragger says:
[snip]

Does this mean it is actually ok to defrag with under 5% spare or
will I run the risk of losing data?

Replace that 4GB disk with something larger.