MacOS Mojave 10.14.3 seems to resolve a bug - startup lag on external USB 3.0 drives!

[the-bigwig]

It's gone now! My iMac was starting up in about few long minutes. White screen was persistent for maybe 3-5 minutes and then gray apple logo showed up and after that iMac starts like it should from the beginning.
With 10.14.3 logo shows up immediately as I press power-on button and iMac starts up like a thunder.

 

[mikehalloran]

T.R.I.M. does not function when a Mac is booted from USB.

No Mac runs as fast booted from USB as it will if the drive is internal or over Thunderbolt.

I boot test drives over USB but never my work. Ever.

 

[astrorider]

I had noticed slow booting for my external Thunderbolt 3 boot drive as well that seems to be gone now too. 3 minutes is a long time to boot these days, but since I don't reboot too often it was a relatively minor annoyance. Nice to know it was a Mojave bug that's now fixed with 10.14.3.