maverick1987 Author

Level 1

34 points

Slow boot time after update to Mojave - External SSD

Hello!

I have a iMac 21" 4k 3,1ghz 2015. I installed an external SSD Samsung 860 Evo 512gb to avoid losing the Apple 1yr warranty if I opened my iMac by myself.

So when I was using APFS format and OSX High Sierra, my iMac used to start, then 2 seconds with a completely empty screen(black) looking for the boot SSD, then the Apple logo appear and it would take another 18 seconds for the system to start completely.

Total boot time = ~20secs.

Now I installed the new MacOS Mojave and my current boot time are very very slow; when I turn on the computer the screen stills black for 2 minutes more or less "looking for my external boot SSD" and then the Apple logo appear and +18secs the system starts.

My current boot time = More than 2~3minutes!!!!

I have also a MacBook Pro 2017 TouchBar and TouchID with 512GB integrated SSD also with APFS format, and update this from High Sierra to Mojave at the same day/time to the iMac. Fortunately the MacBook Pro booting done in about 20secs.

So... There is any solution for fixing this "everlasting" blank screen when booting the iMac with MacOS Mojave and external SSD with APFS format?

I've researched about this, but I can't find anything to solve it. So, I hope someone here may help me!

Thanks!

iMac, macOS Mojave (10.14)

Posted on Sep 28, 2018 8:34 AM

Top-ranking reply

_fiery

Level 1

9 points

Posted on Oct 16, 2018 4:22 PM

I can confirm that just moving my external SSD from USB to Thunderbolt enclosure solves the delay at Mojave startup. I use Delock 42510 (85 EUR at amazon.it + 11 EUR Standard shipping with DHL road) and an Apple Thunderbolt cable (35 EUR).

In my opinion UEFI bootloader either tries to recognize the drive as SSD or wants to read its Firmware revision. This looks like a problem in UEFI and most probably is related to the limit that Apple put on external HDDs to use APFS last year.

Looking at System Information and DriveDX logs, I found several differences. In the Thunderbolt enclosure, drive is recognized as SSD with its Firmware revision, non-Removable, with native S.M.A.R.T. support, Bus Type = SATA, ATA Features = 0x-1, SATA Features = 0x2e. TRIM is not enabled.

In the USB enclosure, drive is not recognized as SSD, it's Removable, there is no Firmware revision, no native S.M.A.R.T. support, Bus Type = USB, ATA Features = 0x20, SATA Features = 0x-1. TRIM is not supported.

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345 replies

Oct 1, 2018 10:00 AM in response to maverick1987

I also have noticed that after upgrading from high sierra to mojave my boot times have increased dramatically.

From about half a minute to nearly 5 minutes!

And i don't use an external hard drive.

The thing is, that my boot times are not consistent.

Around 80% it takes about 5 minutes.

The other 20% it starts like normal in about half a minute.

imac 27" 3.5 GHz i7 (late 2013)

1 TB internal flash storage

16GB RAM

Tried all the typical suggestions, resetting cache and so on. First aid program run on boot drive.

Changed nothing.

Oct 1, 2018 10:58 PM in response to maverick1987

Same issues with external samsung evo 850. Extremely slow boot times. Also had bootcamp and after upgrade, had to completely reinstall windows. Wouldn’t work at all saying there was no boot partition. So far mojave *****.

Oct 2, 2018 9:37 AM in response to Bernard Piller

Bernard you think Apple has a bug to fix if everyone can't boot up in a reasonable time? After Mojave was installed on our iMac at the store 2 days ago, our boot up time is 5+ minutes and our iMac barely functions even after logging in. It takes over 10 minutes to log in.

We've tried all the suggested solutions in this thread and have no external drives. No time machine option either, because the genius bar did the reset and installed Mojave for us .

nivde

Level 1

8 points

Oct 3, 2018 2:37 AM in response to maverick1987

Same issue here, updated my Macbook Air (but did not restart it yet to see if it happens there too) and my iMac 2015 which boots from an external SSD (GDrive bought from Apple Store ): very slow boot times and I have to use the ALT option to choose the external drive otherwise it falls back to the default disk where there's an old version of macOS.

Tried the reset PVRAM stuff, no change.

Hope Apple FIXES THIS SOON !

Oct 3, 2018 4:21 AM in response to nivde

Same thing here. MacBook Pro 15 2013, i7 with 512gb SSD, 16gb memory ram. With High Sierra, 20 to 30 seconds in a cold boot. Now with Mojave, take 2 minutes in Apple logo Screen. And the screen goes blank and comes again. Really don't know what is happen.

nivde

Level 1

8 points

Oct 3, 2018 4:29 AM in response to Isaacwm

Issacwm, I am not sure if you are addressing to me or to maverick1987, but as far as I am concerned, I did not try to reset the SMC too because I have read other testimonials where this did not help either.

MadFisi

Level 1

4 points

Oct 3, 2018 9:02 AM in response to R_Singh

I do not use APFS or TRIM but i stil have the problem. I did not use APFS for Mojave and i did not use it for High Sierra. High Sierra boots in about 10s and Mojave takes at least 4 minutes. I don't think its APFS

Oct 3, 2018 9:20 AM in response to Bernard Piller

Yes it is. It is a shame. SSD take 5 minutes for boot since APFS/Mojave, what is this? Why dont they test it with external SSDs before they roll this update out to the public? It is not unusual to use a external SSD as a boot medium. Time to think about getting back to Windows.

nivde

Level 1

8 points

Oct 3, 2018 12:06 PM in response to Bernard Piller

Did anyone here try the SMC reset? By anyone, I mean anyone with an external SSD issue 🙂

I've been with Apple Support on twitter for the last 4-5 hours and everything failed so far (but I did point them to this thread, maybe it will help speed up the admission of an issue and the fix).

maverick1987 Author

Level 1

34 points

Oct 3, 2018 11:44 PM in response to maverick1987

Hello everyone,

i've found the solution.

The reset of the SMC not work, during the night (all the night) I shutdown the mac and disconnect the power, so the power cord is disconnected for about 7-8 hours.

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 (can be the TRIM functionality that is not present to the USB3 enclosure, even if it supported the TRIM and the UASP functionality.

Thank you for all, my friends !!

R_Singh

Level 1

9 points

Oct 4, 2018 6:30 AM in response to NerdVr

Hi NerdVr,

I tried your method by both fist disabling and then removing the Paragon NTFS software from my iMAC, in fact in my case it had no effect or may be boot an opposite effect as boot time increased or remain same ~ 5 min.

You are luck that it worked with you.

Thanks

denthomp

Level 1

9 points

Oct 5, 2018 3:10 AM in response to maverick1987

Hi any luck with an actual fix yet? Does anyone know if Apple are aware of this, does it need to be reported or would it flag up through this forum?

I have the same problem booting from an SSD, USB 3 external drive - no problem with High Sierra, super fast. Now it's a good 3+ minutes even if holding option to start with.

I lost the whole installation first time round including all my files/apps and had to install fresh! Backed up of course but still a pain.

Will head back to high sierra if no solution soon, shame as really liek the dark mode but ridicoulous Apple have allowed this to happen, and then go on so long without a fix.

Fingers crossed for all :-)

nivde

Level 1

8 points

Oct 5, 2018 4:45 AM in response to denthomp

@denthomp There is an Apple Support on twitter. I had spent about 4-5 hours with them (the reponse time is around 20-30 minutes ) but still did not get to a resolution. In the end i gave up since I had wasted too much time 🙂 And I am almost sure this requires a software update from Apple. So regarding the question if they are aware or not, maybe if more people would go and ask support about the same issue, they will do something about it more quickly ?

nivde

Level 1

8 points

Oct 5, 2018 12:37 PM in response to weeniewawa

I have a question about the SMC reset: every night I unplug my mac (from the wall not from the iMac) and usually I plug it back in next day in the evening after work. Does this count as a SMC reset? Or it has to be exactly 15 seconds + the 5 seconds after plugging it in ?

denthomp

Level 1

9 points

Oct 6, 2018 7:55 AM in response to maverick1987

I have mojave on external ssd, but my internal drive still has high Sierra installed - ssd is set as boot disk but would be interesting to know if everyone else still has high Sierra and this is causing the problem?

Or has anyone tried installing mojave on both internal and external disks and still having the slow boot times?

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Slow boot time after update to Mojave - External SSD