Apple 知識庫提供了一篇與 Mac OS X 磁碟最佳化的文章，若您想要了解在 Mac OS X 上磁碟最佳化或重組的問題，可以參考這篇指南。
Mac OS X systems use hundreds of thousands of small files, many of which are rarely accessed. Optimizing them can be a major effort for very little practical gain. There is also a chance that one of the files placed in the “hot band” for rapid reads during system startup might be moved during defragmentation, which would decrease performance.
文章中也提到，若您使用的是 Mac OS X，其實並不需要進行所謂的“最佳化”，而進行所謂的“磁碟重組”，實際上的用處也不大，除非您的磁碟所剩空間不多，且經常在修改或製作大型檔案 (如編輯視訊檔)。
link: About disk optimization with Mac OS X (Apple)