What is iDefrag?

Defragmentation & Optimization for Mac OS X

Every Mac user has noticed it; over time, your system slows down. This is particularly true in these days of constant security updates, as replacing operating system components not only increases file fragmentation, but also creates a more insidious problem—over time, the operating system itself ends up scattered all over your disk.

This, of course, doesn’t show up as fragmentation—after all, the files themselves are probably contiguous—but nevertheless, it takes your machine longer to start up, it takes programs longer to start, and it takes longer to get your work done.

iDefrag solves these problems and more, by defragmenting and optimizing your Mac’s filesystem.

 - (Coriolis Systems)

Do NOT use iDefrag on an APFS volume and/or an SSD. 

Download iDefrag for Mac

Architecture

OSX Universal Binary

System Requirements

From Mac OS 10.3 up to Mac OS 10.13

Compatibility notes

Emulating this? It could probably run under: QEMU