Problem slow boot with apfs on ssd external

Hello everyone,

i've found the solution.

A friend lent me a ssd thunderbolt drive, which I completely formatted.

With UtilityDisk have created a new APFS partition, and I used Carbon Copy Cloner to do a clone of the entire SSD USB3 to the new Thunderbolt SSD.

After the clone finished I've rebooted the mac, set the new drive as Startup Disk under the settings panel.

After the chime, now the apple logo appear after more or less 10 secs.

The boot time is now reduced from 2-3minutes to complessively about 20-30secs from the chime to OSX.

I've used only the Carbon Copy Cloner app, nothing else; nothing command settings, nothing particular settings.

So, in the conclusion, the problem is the USB3 enclosure.

Thank you for all, my friends !!

The only fix I found is a thunderbolt enclosure for the SSD. Got mine today and boot time is normal, now.
The problem occurs before the Apple logo shows up. It took up to 4 minutes before the logo shows. After that boot time was about 30-40 seconds. With the thunderbolt enclosure it is between 10 to 30 seconds until Apple logo and another 10 to 20 seconds boot time. There have to be some changes with the USB boot loader, because it takes the same amount of time, if I press the ALT key while powering up --- up to 4 minutes with the USB SSD enclosure and a few seconds with the thunderbolt enclosure. Apple, it's time for a fix! I had to spend 106 Euros for a simple enclosure for my System SSD which worked just fine before Mojave!

No, no problems. Both formatted with APFS. All fine after I made the switch to the thunderbolt enclosure.
Since maverick1987 reports the same (he made that switch, too), I guess this is the only way to go for now.
But a pretty expansive one. For 106€ I could have bought another SSD......

In my case the problem disappears in the last Mojave update (10.14.3).

Regards.

Delock 2.5" Enclosure SATA HDD>Thunderbolt external enclosure

Installed an external ssd yesterday. Worked like a charm. Looks like the issue has been fixed in 10.14.3

Yes, I can confirm this: after much a-do during installing the Mojave 10.14.3-update, the start-up is now super-quick: 4 seconds black screen and 1 minute with the apple logo on screen. Very good, Apple!

Considering all the security (EFI) aspects that played probably a role, this is a neat solving of the unacceptable long start-up time. Especially unacceptable because it showed a completely black-screen all the time for 5 minutes ...! That is long, the first time, I can tell you.

But: I am afraid that the update problems will return with every new update, because every restart during the update, it could not find a startup-disk, displaying a blinking ?-Folder and not responding to ANYTHING except a long OFF press. And an Option+ON start to choose the startup-disk. And choosing "OS-Installer" (not the T5) from the list of startup disks. And the same Option+ON again until I could just only choose my external T5 disk.

But I know how to handle it, now. Just happy and a bit exhausted.

Same here. Went from seconds up to 3 minutes until Apple logo shows and another 2.5 minutes until login-screen. Everything was fine and very fast with High Sierra. I use an external SSD in a USB3 enclosure. But I have a longer boot time with the internal SSD in my Macbook Pro Retina 2015, too. I already did a PRAM and SMC reset, checked the drives with Disk Utility and so on.

What can be done?

I recall to have my external USB3 SSD formatted with HFS+ and had the option to keep on HFS+ when installing HighSierra. This worked very well back then.

But still I can not understand, that the Trillion Dollar Company can not afford to test a new OS/filesystem booting of an external drive. I'm not sure, if they even want to fix this problem. Because after all, it's present since over one year when they introduced APFS with HighSierra. I am very disappointed.

Just a thought but perhaps if your internal drive is formatted to HFS it does not work well with the external APFS drive when booting up the external drive. I noticed a similar issue when I formatted an external drive to APFS and installed High Sierra on and tested a few weeks ago when my internal was HFS with Sierra.

I put my SSD in a Delock 42510 Thunderbolt case and the boot delay disappeared.

But this enclosure have two issues:

1. In idle mode SSD heats to 39-40 C (at 20 C ambient). It was ~30 C in the old USB enclosure.

2. The drive increases its S.M.A.R.T. property "192 Unsafe Shutdown Count" every time I issue a "Sleep" command. I have not such problem with my USB case (both cases are powered with external power adapters). I use DriveDx app to read S.M.A.R.T. data.

So, I can't recommend Delock 42510 case. Does anyone have any experience with AKiTiO eSata to Thunderbolt adapter?

I fixed it but its not pretty...

i just took my imac apart and installed the ssd internally.

no delay at all, everything is instant.

Will just a USB3 to Thunderbolt adapter solve the issue I wonder.

Same here.

With AFPS external SSD High Sierra booting done, up to 20-30secs more or less.

Upgrated to Mojave, the booting is now extremely slow, up to 2-3 minutes more or less.

Anyone found solutions ?

Thanks in advance,

Best Regards.

Same here, there must be quite a few people who opted to run the OS from an external SSD rather than risking installing it internally as iMac's are just not very friendly for such upgrades.

I think in High Sierra it only gave you the option to stay as HFS+ if your OS SSD was internal? I dont recall having to force it to stay as HFS+ when I did that upgrade.

Considering APFS has been an option since High Sierra I would have hoped they were aware and found a solution for this by now. From what's been said here though it seems just be to with external (USB?) SSDs. This is similar to trying to run Windows on an external drive, as without a registry edit it cannot find the drive during the boot process.

It is also an annoyance for us Bootcamp users who can now only switch between Windows and OS X by holding ALT down during boot...another thing they haven't resolved yet :/

Sorry I haven't been able to offer any help though.