Defrag with disk utility?

Question

Can anyone tell me how to defrag the harddrive on my Mac? Thanks

Answer 1

I have been using idefrag for some time now and it does a great job. From what I've seen, OS X defrags most of its own system files somewhat efficiently, but it pretty much ignores third party files especially those that are located on drives other than the boot drive. It also seems to ignore some of its own cache files as well. Of course it doesn't matter once a cache file is loaded into memory, but it will take longer to actually load it into memory.
Doing a complete defrag takes a good amount of time though especially if you compact the files. Lately with idefrag I have been using only the "online" option which is a files only defrag and the
"B Tree" option (a select group of system files) with excellent results. This method of defagging takes about 20 minutes instead of hours. Results are equal to or better than the long way.
I will tell you this though: If it were a toss up between idefrag and Disk Warrior for fixing OS X "sluggishness" problems, Disk Warrior wins hands down. A hard drive that is healthy and well cared for will perform well even with a fair amount of fragmentation.
Another thing to be aware of is not all defrag programs are alike and some have been reported to do more harm than good.