Defragmenting Works!

w00t951

macrumors 68000
Original poster
Jan 6, 2009
1,831
6
Pittsburgh, PA
If you feel like your Mac is slowing down, you can defragment - I know all about HFS's built in defragmenting for files smaller than 20MB, but I work with large pictures (40MB+), lossless audio (40-50MB/track), and gigantic video files (3-17GB/file). My drives (external and internal) were completely fragmented.

Even though my ML installation was only a few weeks old, it was starting to feel sluggish when starting applications for the first time. Instead of clearing caches, which actually decreases performance, I used an old purchase of Disk Genius 3 to defragment my external HDD and my internal HDD. Surprise!

Now reading and writing video files is far faster and has less latency. Applications open more quickly. Everything is faster.

As a side note, it appears that HFS's built in defragmenting functions only defragment files, not move them into contiguous blocks - another detriment to performance. Disk Genius didn't find much fragmentation, but it did show that blocks of contiguous files were strewn across my HDD.

Give it a try!

WARNING: DON'T DEFRAGMENT WITH AN SSD - IT WILL DESTROY YOUR PERFORMANCE. OS X WILL USE TRIM AND HARDWARE BASED GARBAGE COLLECTION WITH APPLE SSDS, AND YOU CAN FORCE ENABLE IT HERE.
 

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sk8r1230

macrumors 6502
Aug 3, 2010
342
40
Indiana
do this all the time on my imac. you'll find a lot of non believers but o well. fyi, not recommended on an ssd
 

Aodhan

macrumors regular
Jun 16, 2012
148
0
I am also a firm believer in defragmenting. Even if it is somewhat controversial, it makes me feel better. I use iDefrag, though. It's quite a bit less expensive, but defragging takes forfreakinever.
 

derbothaus

macrumors 601
Jul 17, 2010
4,060
4
You can create a .dmg of your disk and reapply after erasing and have a pristinely compacted defragged drive without any of the dangers of 3rd party reordering or bugs. FYI. Then use diskwarrior for your directory when needed and that's really all you need. And it forces good backup karma.
 

avalys

macrumors 6502
Jun 4, 2004
299
23
I wonder how many people are going to read this thread, and then go off and try to defragment their SSD.
 

w00t951

macrumors 68000
Original poster
Jan 6, 2009
1,831
6
Pittsburgh, PA
I wonder how many people are going to read this thread, and then go off and try to defragment their SSD.
Nice catch. I defragment every time I shut down in Windows. That's how critical I think it is in Windows (along with registry cleaning). I just never bothered with it in Mac OS X.
 

derbothaus

macrumors 601
Jul 17, 2010
4,060
4
Nice catch. I defragment every time I shut down in Windows. That's how critical I think it is in Windows (along with registry cleaning). I just never bothered with it in Mac OS X.
Why not use Diskeeper and never worry about it?
 

Queen6

macrumors 604
iDefrag is about the best in the business for OS X and it does work on systems that have very large files or are short on disk space. Typically I will only defrag OS X once or twice a year.

As for SSD`s you wont hurt your performance in the short term, however nor will you benefit, what you will do is potentially reduce the performance over the long term, only possible benefit i can see is free space consolidation little else. Equally if you chose to run the likes of iDefrag once every year or two i seriously doubt it would have any significant detrimental effect on the drive, and you would likely consolidate free space in the process.
 
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