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nayan504

macrumors member
Original poster
Dec 17, 2009
33
0
Hello... I am trying to defragment the hard drive using snow leopard but I get the following message:

You cannot use this algorithm on the selected volume. Off-line algorithms need to unmount the disk so you need to boot from a different disk, partition, computer or CD/DVD. Alternatively, use the Quick (on-line) algorithm.

How would I do this without doing a quick algorithm? Basically how do I unmount the disk or boot from a different disk or DVD and run this program, iDefrag. Thank you
 
the reason i want to do it is because boot camp keeps saying..some files cannot be moved and some threads stated that I should defrag the system
 
Personally, I think you would be better off cloning your system, erasing your HDD and restoring the clone. That method is almost certain to work. Using iDefrag has worked in some cases, but certainly not in all cases. The problem isn't strictly that your HDD is fragmented, it is that your free space is not contiguous. Using iDefrag may or may not correct that problem.

I have not used iDefrag before, but your error message seems to indicate you cannot defrag the volume you boot from.

Woof, Woof - Dawg
pawprint.gif
 
how would i perform this clone? is there a program that will do this for me?

also will it restore my computer to what it was before? thanks
 
I'm one of those who believe - regardless of what Apple says - that periodic defragmenting and optimization of a volume is a worthwhile task to do.

You should be aware that you CAN'T use a boot volume to "defragment itself". That's like asking a surgeon to do brain surgery on himself.

You have to boot the Mac from ANOTHER volume, and then "attack" your original volume with the defragmenting software.
 
Periodic defragmenting isn't a bad idea, but if you're like me and you do a fresh install every 6-12 months, it's not very necessary. Plus the OS itself does a form of defragmentation where it pulls sectors from the inner portions of the disc and rewrites them to the outer portions. It's not, from my understanding, a pure defragmentation as I don't think it does all of the reorganization that something like iDefrag would, but it works just fine and keeps the system running faster than without.
 
"if you're like me and you do a fresh install every 6-12 months, it's not very necessary."

Off-topic comment:
Why would anyone want to do "a fresh install" every 6 months?

This message is being typed on a PowerMac g4/1.25 MDD assembled in March of 2004.

When I got it, I immediately partitioned the drive, and re-installed from the System dvd (was OS 10.3.2).

As the periodic system software updates were released, I installed them, but that ended with the release of 10.4.

Since that time, it is still running on THE ORIGINAL SOFTWARE INSTALLATION of 2004. I have NEVER had the need to "re-install the System" in SIX YEARS. Still run great.

Again I ask - why go to the trouble of re-installing the OS every 6 months?

- John
 
For some it is a carryover from the days of having to do it on Windows
They just feel more comfortable with it
They feel it increases performance
Whether it does or does not is a matter of opinion and mostly perception

I don't see the need to do it either
I have been using Macs since 1987

Woof, Woof - Dawg
pawprint.gif
 
For me it's because I run two companies and several individual endeavours on one machine. I test out a LOT of software weekly, and am constantly switching to new things, archiving and removing projects, etc. Deleting things is never entirely thorough, so every 6-12 months it's easier to just do a clean install than spend hours looking for all the unnecessary files and bits and pieces left behind.

Plus I run on OCZ SSDs that are not currently GC supported, so I like to blank out the zero data from time to time, it helps with keeping them running smoothly.

EDIT TO ADD: also, maybe your laptop runs perfectly. I did a fresh install on an ibook that I've done the same with (install and update/upgrade) since buying 5 years ago, and it ended up feeling around 2X faster. Could be my imagination, but either way I'm happy with it again...
 
You don't need to. The Mac filesystem doesn't experience fragmentation-related performance issues.

Not performance, but it does interfere with Boot Camp's attempts to partition the drive. Mac does in fact experience many issues regarding fragmentation.
 
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