Starting up from external SSD takes long time (and doesn't always work)

[Beliblis]

Hi,

I want to run my new 2018 Mac Mini from an external SSD. I purchased a 1TB Samsung m2 drive, and this enclosure:
https://www.amazon.co.uk/FIDECO-External-Enclosure-Adapter-Transfer-M-2-SATA-NGFF/dp/B07TTG66GW/

The external SSD is password-protected and running Mojave (can't go Catalina quite yet because of some sofwtare & Wacom driver issues).
The internal drive is untouched, running a clean Catalina install.

Whenever I restart the machine, it seems to take an awful long time, before the machine gets going, with the screen (attached via USB-C) not getting any signal, quite often for several minutes. And if the machine doesn't boot, I turn it off, turn it on again and then the machine goes into Recovery Mode (from the INTERNAL drive), telling me I must have forgotten my password and that I should enter a new password.
I then click restart, the machine boots up from the INTERNAL drive. Once Catalina is up, I select the EXTERNAL drive as a startup volume, and restart. And again: it takes a very long time for the screen to even show an Apple... and since I don't know IF the machine is about to boot at all, I sometimes get impatient, turn it off & on again -- just to find myself in recovery mode again.

With my old 2012 MacMini, this never was an issue.
Once the external SSD system is up and running, I don't have any issues though.

Currently, the SSD is attached to one of the USB-Ports. I tried a Thunderbolt/USB-C port, but that didn't seem to help.
Could it be that there's a problem with that specific enclosure? Or maybe the fact that FileVault is enabled on it?
Or is it normal for the new Mac Minis (or new OS) to take longer to start up/recognise an external drive?

 

[Fishrrman]

That's a USB3.1 gen2 enclosure.
You want it attached to a USBc port.

If you connect it to a USBa port, it's only going to run at "half-speed".

Dumb question:
Have you gone to the "startup disk" preference pane, entered your password, and then set the external drive to be the boot drive?

Final thought (and it's important):
The 2018 Mini internal SSD has read speeds about 3-4 times as fast as the external boot drive.
Why aren't you booting from that?

The external enclosure you bought will NEVER run anywhere near as fast as the internal SSD.

 

[Juicy Box]

I have read about people, and I think I have experienced (honestly can't remember) slow boots with a SSD connected using an USB3 enclosure.

Once it boots, everything runs fine with the speed one would expect, but the boots are really slow.

Is it formatted with APFS or HFS?

If it is not in HFS already, I would try reformatting the external drive in HFS and see if your issue improves.

 

[Juicy Box]

I forgot to mention that everything I have read about the external SSD slow boot issue was using USB, I think TB is unaffected.

 

[getrealbro]

@OP, the following is good advice...

...Final thought (and it's important):
The 2018 Mini internal SSD has read speeds about 3-4 times as fast as the external boot drive.
Why aren't you booting from that?

The external enclosure you bought will NEVER run anywhere near as fast as the internal SSD.

I was planning to boot my 2018 i7 Mini w/ 256GB SSD from my Samsung 1GB T5, until I ran these speed tests...

GetRealBro

 

[Beliblis]

That's a USB3.1 gen2 enclosure. You want it attached to a USBc port. If you connect it to a USBa port, it's only going to run at "half-speed".

Yes, I know. The reason I have it attached to the USB3 port is just temporary, until I have a "proper" USB-C cable: The enclosure came with a USB-C-to-USB3 cable and a USB3-to-USB-C adapter. Depending on which side I put the adapter, the drive won't turn on at all. That's why I thought the actual cable may be the problem.

Dumb question:
Have you gone to the "startup disk" preference pane, entered your password, and then set the external drive to be the boot drive?

Yes

Final thought (and it's important): The 2018 Mini internal SSD has read speeds about 3-4 times as fast as the external boot drive. Why aren't you booting from that?
The external enclosure you bought will NEVER run anywhere near as fast as the internal SSD.

Various reasons:
1) Apple prices for 1TB are too expensive
2) If the Mac Mini dies (or needs to be repaired), at least I still have my operating system and data. Happened to a friend of mine: his MBP with soldered-on drive died whilst being on a job. 1/2 the data from that day is lost. (He does run backups in the evenings though).
3) Burglery/theft: It's a lot easier to hide the small external drive. Not a major reason but a benefit.

The external enclosure will run fast enough for now, and as soon as the Samsung X5 (or any other Thunderbolt enclosures) becomes more affordable, I'll get one of the base models and stick my current 1TB SSD into it. Read/write speeds are more than decent, certainly good enough for video editing:
https://forums.macrumors.com/thread...-external-ssd-for-a-reasonable-price.2161812/

 

[IowaLynn]

@OP, the following is good advice...
I was planning to boot my 2018 i7 Mini w/ 256GB SSD from my Samsung 1GB T5, until I ran these speed tests...

GetRealBro

HFS+ is going to be slow, APFS is designed for SSD. Aren't there some issues with the Samsung T5?

 

[Beliblis]

If it is not in HFS already, I would try reformatting the external drive in HFS and see if your issue improves.

It's in APFS – as far as I remember that was the only option that came up when I formatted the drive from within the MacMini's original Catalina system.
Isn't APFS also the recommended file system for SSDs?
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@getrealbro
The guy in this link gets read and write speeds above 2000 MB/s:
https://forums.macrumors.com/thread...-external-ssd-for-a-reasonable-price.2161812/

 

[Juicy Box]

Isn't APFS also the recommended file system for SSDs?

APFS is going to be faster, but if HFS fixes your boot problems, maybe it might be worth sacrificing some read/write speeds to boot faster.

BTW, I don't know if formatting to HFS would fix it, I am just saying that it might be worth a try.

I haven't used Mojave nor Catalina, but IIRC, HFS does work for Mojave. I am not sure about Catalina.

 

[getrealbro]

HFS+ is going to be slow, APFS is designed for SSD. Aren't there some issues with the Samsung T5?

My T5 is attached via USBc and partitioned into: System (256GB AFPS) and Data (744GB HFS +). The internal is a single partition: System (256GB AFPS). The speed tests were done when booted on the appropriate System e.g. the T5 Test was done when booted from the T5’s System partition.

I’m not aware of any issues with the T5.

GetRealBro
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@getrealbro
The guy in this link gets read and write speeds above 2000 MB/s:
https://forums.macrumors.com/thread...-external-ssd-for-a-reasonable-price.2161812/

Have you confirmed that you are getting similar speeds via Black Magic Disk Speed Test? IIRC those speeds require both an NVME SSD and USBc (Thunderbolt 3) port.

GetRealBro

 

[Juicy Box]

My T5 is attached via USBc and partitioned into: System (256GB AFPS) and Data (744GB HFS +).

Could you post R/WR speeds from both partitions of the external drive? I am curious if there is a significant difference between the two file systems.

 

[IowaLynn]

https://bombich.com/kb/ccc5/working-apfs-volume-groups

 

[blueprint1983]

How long is your start-up time after the chime?

What are the specs on your Mac Mini?

Did you clone your external drive or is it a fresh install?

I literally just did this same thing but with an iMac and a 2 tb SSD T5 drive and I'm running flawlessly (Catalina, APFS). I followed mostly what Fishrrman advised.

https://forums.macrumors.com/threads/late-2012-imac-external-ssd-upgrade-qs.2214404/

 

[fastlanephil]

Hi,

I want to run my new 2018 Mac Mini from an external SSD. I purchased a 1TB Samsung m2 drive, and this enclosure:
https://www.amazon.co.uk/FIDECO-External-Enclosure-Adapter-Transfer-M-2-SATA-NGFF/dp/B07TTG66GW/

Are you saying you bought the 2018 Mac Mini new with Catalina already installed?

 

[getrealbro]

Could you post R/WR speeds from both partitions of the external drive? I am curious if there is a significant difference between the two file systems.

System: i7 Mini running Mojave 10.14.6 on the internal 256GB SSD. Targets: Samsung T5 connected to USBc port with two partitions: AFPS and HFS+

GetRealBro

 

[Fishrrman]

OP wrote:
"1) Apple prices for 1TB are too expensive
2) If the Mac Mini dies (or needs to be repaired), at least I still have my operating system and data. Happened to a friend of mine: his MBP with soldered-on drive died whilst being on a job. 1/2 the data from that day is lost. (He does run backups in the evenings though).
3) Burglery/theft: It's a lot easier to hide the small external drive. Not a major reason but a benefit"

I don't see these reasons as being important enough to run a slower drive instead of a faster one.
You can still boot from the internal drive, keep your apps on it, and basic accounts, yet keep all your important data on an external drive.

You can set up the external with 2 partitions:
Partition one -- bootable cloned backup of the internal drive. Now you have a second boot source. You would want a cloned backup anyway.
Partition two -- all your data, including "large libraries", etc.

An external SSD is just as susceptible to failure as an internal SSD. Maybe moreso.
I've had a couple die on me already.
Just "went dark", never to be seen no mo'.

Just wondering ... how warm does the external drive get in normal usage?

I'm perhaps the greatest advocate in this forum for using an external SSD boot drive when the internal drive is slow. I booted and ran my 2012 Mini for SIX YEARS this way.
BUT... I see no sense at all in having a FAST internal SSD (which the Mini now has), and booting from a much slower external SSD instead...

 

[getrealbro]

...
You can still boot from the internal drive, keep your apps on it, and basic accounts, yet keep all your important data on an external drive.

You can set up the external with 2 partitions:
Partition one -- bootable cloned backup of the internal drive. Now you have a second boot source. You would want a cloned backup anyway.
Partition two -- all your data, including "large libraries", etc.
...

This is exactly how I have my 2018 Mini, w/256GB internal SSD and 1TB external T5, setup.

GetRealBro

 

[blueprint1983]

That makes three of us.

If he did a clean install I wonder if the issue lies with the fact there is no recovery partition like he would have if he did a clone.

 

[Beliblis]

An external SSD is just as susceptible to failure as an internal SSD. Maybe moreso.

I've had computers die on me where the hard drive was still OK (late 2011 MBP for example). Of course, the MacMini doesn't have a dGPU – so less likely to fail. Still, the power supply could fail (as it did in my G5 tower at the time), or anything else.
I also had hard-drives die on me which I could rescue at least some data from. So, all in all I'm far more comfortable with an external hard drive (which btw has a recovery partition).

Just wondering ... how warm does the external drive get in normal usage?

No idea – I've been trying to find a temperature monitor software that does this. Any suggestions?

I'm perhaps the greatest advocate in this forum for using an external SSD boot drive when the internal drive is slow. I booted and ran my 2012 Mini for SIX YEARS this way.
BUT... I see no sense at all in having a FAST internal SSD (which the Mini now has), and booting from a much slower external SSD instead...

Again – I don't think the external m2 will be "much slower" for long. At the momen, yes, it is much slower. But as soon as I put it inside a x5 enclosure, I'm pretty sure things will be just fine.
The attached screenshot is my external APFS-formatted drive with USB-C connection. This is with an external X5 enclosure as discussed in this thread here. Soon there'll be other Thunderbolt enclosures available.

@getrealbro Seen your diskspeed screenshots. Very strange that your T5 is so much slower than my 'no-name' enclosure.
🤔

 

[getrealbro]

...
@getrealbro Seen your diskspeed screenshots. Very strange that your T5 is so much slower than my 'no-name' enclosure.
🤔

It’s not clear to me exactly what “1TB Samsung m2 drive,”you have. But I’m guessing it is an NVMe PCIe SSD. If so, it should easily beat a Samsung T5, which is a SATA SSD and only advertised to get 540MB/sec. So my T5 is performing very close to spec. And your "1TB Samsung m2 drive" in a "no-name" enclosure is getting 40-50% of the performance of an X5.

Attached is a table which compares the Samsung T5 (SATA) and X5 (NVMe PCIe) SSDs curtesy of the Verge.

https://www.theverge.com/2019/5/13/...rbolt-3-usb-c-samsung-x5-t5-specs-test-how-to

GetRealBro

 

[Beliblis]

Ah, ok. Sorry, my bad. Didn't realize the T5 is SATA. I thought it's some sort of "smaller brother" of the X5.