Fragmentation

Hi, I'm a new mac user, coming from windows I didn't believe that there is no fragmentation in mac os, so I installed an app called drive genius 3.0.1

I've only used mac for almost a week (of course I transferred all my files, some 250 G, including some HD movies), but Drive Genius shows that there is already 58% of hard drive fragmentation.

so how come that everything I read about Mac OS X says that unlike windows, there is virtually no fragmentation in this OS??

thanks, just wanting to learn more about macs.

Every OS has fragmentation, it can not be avoided.
It is true that OS X is less prone to fragmentation compared to other OS's, but you will still have hard drive fragmentation and file fragmentation.
58% after one week is a lot though.
There are a number of threads on the forum related to fragmentation as there are huge differences in opinions on how important fragmentation really is.

Cheers ... McBie

ok, thanks
anyway
im not planning on buying drive genius...at least in the mean time
do u know any free defragmentation app??

I don't think anyone is giving away defrag apps. One stand-alone is iDefrag, which I believe is priced reasonably. Yeah, they say you don't need to do it, but I do it anyway, with TechTool Pro.

If you maintain at least 20% of free space, fragmentation will not be an issue.

About disk optimization with Mac OS X

thanks guys...it seems i need to defragment...its a shame mac os x doesnt come with an utility for that.

t4ggs said:

thanks guys...it seems i need to defragment...its a shame mac os x doesnt come with an utility for that.

Click to expand...

Usually it's not needed, however, if you do want one, I suggest "iDefrag". It's only $29.95 and it can defrag without using a boot disk.

Regards.

t4ggs said:

thanks guys...it seems i need to defragment...its a shame mac os x doesnt come with an utility for that.

Click to expand...

Why do you "need" to? Is your system drive that close to capacity?

cwa107 said:

Why do you "need" to? Is your system drive that close to capacity?

Click to expand...

yep only 6% free
anyway if it wasnt...the disk is still fragmented so whats so the deal with how much spare space do i have?

You may not even be able to defrag a disk that only has 6% free space. In windows you almost certainly wouldn't be able to. There's not enough free space for a defrag utility to be able to move the files around that it needs to.

You should never run any system partition with less than 15% free space.
I start looking for a larger drive when I hit 30% free space.

When you start hitting that amount of free space there are several things happening.
The armature of the drive has further to go to get the data off the disk.
While files themselves may not be fragmented, apps that require multiple files when they open are having to look all over the drive to find them.
The free space becomes fragmented. This is really the issue I've been seeing with OSX regarding fragmentation. OSX does a really good job at keeping files together. As you add and delete files from the drive, you end up with free space all over the drive. This causes your new files to become fragmented because there is no where on the drive to put them in contiguous space.
You have no contiguous free space available for virtual memory. This also is going to slow down your experience as the drive is having to move all over the place to write and obtain your data.

t4ggs said:

yep only 6% free
anyway if it wasnt...the disk is still fragmented so whats so the deal with how much spare space do i have?

Click to expand...

Generally speaking, as long as you have roughly 20% of your disk free, fragmentation is a non issue. But don't take my word for it, see Apple's article I linked to previously

Get an external hard drive for your HD movies, then you won't have to worry about it. You should never let a harddrive get to 94% full.

I have a post detailing my experiences with fragmentation on OS X and links to a couple articles that discuss fragmentation it in some detail.
http://www.mac-forums.com/forums/os...87952-defragging-os-x-discussion-example.html

Most certainly you will see a performance hit if your drive is severely fragmented. I mentioned in that link above that I had a Powerbook that was taking over 5 minutes to boot. It was actually in excess of 15 minutes (I found a much earlier post I had made when I had that problem… it was more accurate). There are other scenarios… that post details them better.

But as has already been said, your bigger problem is the amount of free space available. You really need to address that before trying to defrag it. With so little space, defragging would take forever, and probably even wear down your drive more.