APFS High SIerra Guest Why not?

[TECH198]

Using Fusion 10.1.3, i noticed when installing High Sierra as Guest, it doesn't use APFS... Why is this ?   Is that because you'd see very little benefit over a psychical  as its already a virtual drive ? or the simple fact it doesn't emulate an SSD, just a traditional HD ?.(probably the reason)

[ColoradoMarmot]

You guessed right, Apple only installed APFS as bootable file systems on physical SSD drives because it actually slows things down on a physical drive.  Snapshots in particular are an issue (I'm not a fan of the implementation).