Should you defrag your Mac? I speak to many Mac users that often ask, “Do I really need to defrag my hard drive on my Mac” and I always tell them “absolutely”. The benefits include faster seek times to access files, quicker boot times and over time it reduces wear on the drive because the read/write heads do not need to travel as much across the media when searching for a file.
Now, to address Apple’s view and look at this debate objectively I did a little searching on their support site and found that they have archived this support article in 2010. If you read down through the main bullet points of this document you quickly realize that it refers to Mac OS X 10.2 and 10.3 Panther. One could assume that referencing file fragmentation and those older operating systems Apple cant be addressing todays modern Intel based Macs and hard drives. The article continues and touches on “Hot-File-Adaptive-Clustering”. However this primarily helps with slow growing files, which back then were much smaller in size as well as the capacities of the drives. Apple also mentions read-ahead and write-behind caching would reduce the perceived system performance and again this is during that time era when files were simply not the sizes of what most users and professionals deal with today.
In other web searches I found Wikipedia mentioning HFS Plus was introduced in 1998 to accommodate larger drive size drives among other aging features that HFS did not support. A number of optimizations were needed to the allocation algorithms to attempt to defrag files while they are being accessed without a separate defragmenter tool. These optimizations helped and decreased fragmentation of smaller files overall from previous file system versions but ultimately never eliminated the potential of fragmentation altogether. If your volume becomes fragmented, the only way to truly defragment your drive is to use a 3rd party utility such as Drive Genius 3 or or to wipe the hard drive completely and install the system from scratch. Backing up a complete drive and then formatting it and restoring files is simply not a convenient way to do this on a regular basis.
The Defrag feature in Drive Genius 3 reorganizes the fragmented pieces of all files and compacts their content into one contiguous block for faster access times. Reorganizing the files into one continuous block improves access time for the file to be opened. Compacting the files allows new files to be written onto the hard drive without data fragmentation. As you can see the screen shot below of Drive Genius 3 ‘s defragmentation map viewing the “FIle Fragmentation” of a Mac OS X Lion Mac HD, there are several files that are 25KB, 34KB 24KB, 28KB in size. This would indicate that the HFS plus file system is not defragmenting all smaller files as one would expect and is in direct contrast to the rumors that state otherwise. In the next screen shot the volume is 6% fragmented(0.9% of total space) and does not need to be defragmented, however this Lion installation is only 2 weeks old. If you visualize reasonable file access over time you can easily conclude that file fragmentation occurs frequently and often. In conclusion, please note that my research is not scientific and I am simply attempting to address that file and volume fragmentation occurs and it is compounded with the larger files and drives we use today on a modern Mac. Apple’s Disk Utility is an excellent operating system utility however, its missing a “defragmentation” tool.
Drive Genius 3 includes the popular defrag tool, used by many IT professionals, videographers , photographers and thousands of happy customers around the world. The degrag tool is one of many features that make Drive Genius 3 a complete hard drive maintenance tool. For more information visit Prosoft’s website / or call our technical support team for details. (925) 426-6306.