Problem slow boot with apfs on ssd external

Hi

I have a problem with apfs on my ssd external that I use for boot.

With High Sierra and both Mojave, booting from external ssd apfs is long (2 or 3 minutes)

Using HFS Journaled in High Sierra the boot is about 20"... But with Mojave it isn't possible using HFS.


So, the problem is APFS with external SSD


Any solutions?

Thanks

iMac, macOS Mojave (10.14), iMac 21,5'' 2018

Posted on Sep 27, 2018 1:21 AM

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Posted on Dec 23, 2018 9:40 AM

I had this problem also since 10 nov 2018 when I bought a Samsung T5 500GB SSD and installed Mojave on it. Sometimes 4 minutes black screen before the AppleLogo appeared! Totally unacceptable, although workable... But I think i solved it. The problem appears to be that installing and updating the Samsung T5 Firmware needs at least one explicit eject and re-attach of this (external) SSD. But that is not possible while it is the disk where upon the OS is working! And re-assigning another disk to be the startup-disk does not count as a formal eject of the T5-ssd, because the restart takes place immediately without ejecting the ssd (so it seems). The solution:

  1. Make (or use) a different, bootable startup disk, change startup-disk to that particular disk en Startup
  2. Then update (safety first) the firmware on the still attached T5 ssd and EJECT and re-attach the T5 ssd (several times, if you want to be sure)
  3. Assign Startup disk back to the T5 and Startup. This will take long, the first time, but there-after the slow-boot problem is gone!


Everything is probably caused by the fact that I had NOT activated the T5 SoftWare and FirmWare + ejected and re-attached the T5 BEFORE putting a new macOS on it. I did that deliberately, because I thought Mojave would know best how to format and install itself on this tiny little gem. That is true, but every time Mojave tried to re-start while installing etc. it got lost in space, because the T5-firmware was not effectively installed... And while working on the T5, we all could not eject it ... because it was the disk with the active OS on it...

So: an unsolvable loop. Which will come back every time when you update the firmware ! Because this firmware is not really designed for a bootable external ssd. And that is probably caused by the necessity to make attaching the data as secure as possible (that is what the T5-password-software tries to achieve).

Thus: first formatting and installing/updating the firmware on the T5 and immediately ejecting and re-attaching it is necessary. Mac Mojave will then re-format the ssd to APFS while installing, but the firmware is then already safely working in this little thing.


45 replies

Oct 1, 2018 11:56 AM in response to Scanapix

Exactly the same problem on my external USB SSD. Very slow boot 1-2 min. since Mojave upgrade. On High Sierra with HFS+ the same drive started in ~20 sec. In Mojave from start to boot menu (holding Option key) takes ~30 sec. Then from boot menu to Mojave desktop 1-2 min.


My other problem is that my Recovery partitions disappeared after Mojave upgrade. My SSD is now formatted - first partition HFS+ (El Capitan), second partition is APFS with Mojave. No Recovery volumes appear in the boot menu. Booting to El Capitan (on the first HFS+ partition) is also slow (30 + 20) sec.


The Thunderbolt case allows TRIM command to pass to SSD, while USB case prevents the TRIM to reach the drive. There are a lot of users that complain about slow boot with APFS on High Sierra as well. Some claim that boot time is slow after enabling TRIM, others that after disabling TRIM. Another user restored his boot volume from Time Machine and his boot time reverted to normal.


I will try complete format and restore from backup, but I suspect that APFS requires TRIM to work.

Oct 1, 2018 1:23 PM in response to _fiery

Mojave requires APFS, but APFS does not require TRIM to work. Boot time got fast as soon as I put the SSD into the Thunderbolt 2 enclosure. I activated TRIM after that. As I understand it, TRIM is write-only and boot time is only affected by read-times. My SSD was pretty fast without TRIM. And it was still pretty fast with USB3 after log-in. The problem is the dark screen before Apple logo. I could live with the 40 seconds after that, but I cannot live with the 4 minutes plus before the Apple logo appears. The enclosure was pretty expansive: 106€ for a metal case with a pretty small board in it. I was lucky enough to at least have a thunderbolt 2 cable already.


Tommorrow I will try something. I will hook up my external SSD in a USB3 enclosure at my wifes Mac Mini. The Mini has not been updated to Mojave an runs on High Sierra. I want to have a look a what happens during the time before the Apple logo shows. The interesting part is, that my Macbook Pro shows long boot times even when I boot from the internal SSD with the USB3 SSD connected. And all my other drives start working, too (ie. the backup drives, although they lack a boot partition). Isn't that strange?

Oct 3, 2018 8:03 AM in response to Amaros

I wonder if Disk Utility shows "Solid State Drive: yes" for your SSD (in thunderbolt case). In Disk Utility select the drive, then Cmd+I to show Information window. My drive shows "Solid State Drive: no", but it's in a USB 3.0 case.


Also, do you see any Recovery partitions when you hold the Option key at startup?

Oct 6, 2018 6:26 PM in response to Scanapix

It seems that this problem is not new. I tested rEFInd boot manager on my Mojave USB SSD and it's very slow, too. But I found that a user (see Uncle Sam post) in 2013 that fixed the slow boot problem by placing rEFInd boot partition on his internal HDD:

https://sourceforge.net/p/refind/discussion/general/thread/bc570433/#625f


I also noticed that boot is very fast if I force shut down (holding 5 sec.) the power button. Not a fix though.

Dec 26, 2018 1:09 PM in response to PCzzz

@PCzzz, I'm glad you resolved it for you, but I don't see why ejecting the drive would make a difference. The drive basically gets ejected when you reboot or shut down the computer.


Based on what you said, I booted to the old, internal drive, installed the T5 software and it found a firmware update since the last time I had done this. I installed the firmware, ejected the drive just for the heck of it, and then rebooted. The problem seemed to be gone! The computer chimed, and I could see it accessing the T5 twice, then it quickly found the T5 as a startup volume and booted up. However, when I shut down and powered it up later, the startup delay was back.


I did file a bug report with Apple on this; we'll see what they say.

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Problem slow boot with apfs on ssd external

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