10.13 NetBoot Images take 8+ minutes to boot

Number:rdar://34251768 Date Originated:05/09/17
Status:Open Resolved:
Product:macOS Product Version:10.13
Classification:NetBoot Reproducible:Always
10.13 NetBoot images created with SIU from a beta 8 or 9 source take 8+ minutes to boot.

Steps to Reproduce:
1) Create a NetBoot Image with SIU with a Beta 8 or 9 APFS volume as the source
2) Time how long booting to the NetBoot takes (from boot to loginwindow).

Expected Results:
10.12.x same hardware is 3-4 minutes

Actual Results:
8-9 minutes but boot does complete


In my testing the source DMG was created with AutoDMG


Issue persists in release

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