External NVMe drive spontaneously dismounts

[mikehalloran]

External drives unexpectedly dismounting is a problem I've had with every Mac I've ever owned.

I've been complaining about or responding to that around here for 20 years or so—ever since my 2002 G5. It's been storage over USB and FW, however, never, ever Thunderbolt or Ethernet (for Time Machine) or SCSI on my Mac Plus–G4. The responses were often along the lines of "I've never seen that…". There was another recent thread complaining about this exact issue.

USB4 may have the same speed rating as TB3 but as you have seen, it has that old USB external storage issue. A TB enclosure has been certified by Intel. You never used to see that mentioned because it was never an issue. Apparently, USB4 has made Intel certification important. Again: "Thunderbolt compatible" is not Thunderbolt.

I have TB2 (through the TB2-TB3 adapter) and TB3 storage attached to my iMac Pro. Thunderbolt has been absolutely rock solid.

That WD Black you bought and the Crucial P2 are rated 2240Gbps—expect around 2000 in a 4 lane TB3 enclosure. The 970 EVO and similar drives are rated 3600 but they also run a lot warmer—expect 2600-3200 in a 4 lane TB3 enclosure. If putting it into a 2 Lane enclosure certified to be TB3, do not waste your money on a 970 EVO since those SSDs are already faster.

My TB2 dock has a pair of 8TB SATA III SSDs in it. Speed is rated 560Gbps and real world is probably around 480. That's fast enough for samples and archiving but if I try to bounce a DP file that I've archived on it, I sometimes get the hesitation that people used to complain about—I've always chalked that up to timing differences between internal storage and external that's about 1/13 the RW speed—bounce always completes, though. If I'm simply creating a new mix, I don't mind since moving the project back onto my System drive takes takes longer.

The reason I keep Kontakt and SampleTank on my System drive is that load (NI) and rebuilding the index (IK) can take much longer but once done, VI streaming feels the same.

One more thing: Move your AppleMusic (used to be iTunes) library to the external. When done, hold the Option key the first time you launch Music.app and navigate to that new location. Easy. Since Mojave, no simlink or alias.

[James Steele]

Yeah. I don’t know if I have much iTunes on this Mac. I have zero photos on it.

Been doing okay with a different cable. We shall see.

[mikehalloran]

If it works, declare victory.

[James Steele]

If it works, declare victory.

I hope so. The other cable was a cheapo. I replaced it with an “Intel Certified” TB3 cable I had bought anticipating the arrival of the UAD2 TB3 Satellite:

[Intel Certified] Cable Matters 40Gbps Thunderbolt 4 Cable 2.6ft with 8K Video and 100W Charging - 0.8m, Compatible with USB4, Thunderbolt 3 Cable and USB-C
https://a.co/d/7AJqRRt

Maybe I’ll get lucky and this will hold. If so I’ll order another one for the Satellite.

[Michael Canavan]

If it works, declare victory.

I hope so. The other cable was a cheapo. I replaced it with an “Intel Certified” TB3 cable I had bought anticipating the arrival of the UAD2 TB3 Satellite:

[Intel Certified] Cable Matters 40Gbps Thunderbolt 4 Cable 2.6ft with 8K Video and 100W Charging - 0.8m, Compatible with USB4, Thunderbolt 3 Cable and USB-C
https://a.co/d/7AJqRRt

Maybe I’ll get lucky and this will hold. If so I’ll order another one for the Satellite.

Considering that TB4 has circuitry in the cable this could 100% be the solution.

All of this begs the question as to why Apple decided to have a user determined unmount routine for external drives? Microsoft protocol on drives is pull the cable, drive unmounts, supposedly no damage done. In day to day experience over the years USB 3 has had an issue of just randomly unmounting depending on the weather, Mac OS version, etc. Sometimes even getting unmount error messages with the drive still mounted, suggesting a momentary glitch in connection can lead to the OS raising a red flag etc.
So USB is less stable on Mac OS for external drives, and I'm at this point looking at Apple, since my PC friends are all perplexed by Apples rigid unmounting protocol, and end user experiences with USB3+ in general. I do not hear this complaint from the other side, and IMO it's on Apple, since literally recently a USBC drive with an NVME blade would unmount after a couple minutes on the M1 Air, worked fine on a PCI USB3 card in a Mojave Mac Pro, and was magically fixed by an OS update to Monterey.

Anyway that's only peripherally related to your issue, IMO it could easily be a cheap cable causing problems if it was attempting to navigate to TB4 protocol on an uncertified TB4 cable.

[James Steele]

Well it wasn't the cable. All of this is kind of pissing me off frankly. Thought I'd be smart and get an enclosure that was recommended by several YouTubers and I was getting awesome speeds, but today I went and booted the Mac Studio and the drive was not on the desktop. I restarted. It wasn't there. I had to unplug and plug the drive and then it appeared on the desktop.

Seems like once it's mounted it seems to be okay. But again... ticks me off. I don't want to be a certified TB drive because I can't find empty enclosures... they call come with an NVMe inside them and I don't need another. So I'm gonna step down from the 2700MB/s to 1550 MB/s with the OWC solution... which is fine. I just liked the quick loading of sample based VIs. It was fun to browse instruments on my Komplete Kontrol S61 Mk2 and load different VIs right after each other... boom, boom, boom... fast... while auditioning various sounds.

I feel pretty defeated at this point. I *could* possibly return the WD SN-770 as well as the enclosure and then go for a "Intel certified" drive like Mike linked to. They don't get 2700 MB/s but close. Or just punt and get the OWC unit and return the enclosure. Don't know how often you can return stuff on Amazon, but I must be setting a record for returns over the course of getting this new setup going.

[James Steele]

Just was reading some of the reviews at Amazon the Intel Certified enclosure:
https://www.amazon.com/Certified-TEKQ-T ... 09QW41KK6/

I started reading reviews and it appears some people had dismounts with this drive possibly. Here's a quote from the review, but I found the second one very interesting. On reviewer wrote that some of these NVMe drives draw more power than others and if there's any fluctuation of bus power they will not be seen by the Mac. He said his WD Black driver randomly disconnected but the WD Blue (which has a lower power requirement, doesn't). It's an interesting theory.

disk ejects itself strangely. Mac shows "disk not ejected properly". Can you tell me why?

Most NVME power requirements are at the edge of the available bus power not including the small amount needed for the PCB/controllers ect. Because of this any fluctuation in power will cause the disk to reboot. The Mac sees it as a disconnected drive. I have since switched to using WD blue NVMEs are their power draw is among the lowerest. None of my blues eject themselves just the blacks randomly.

[James Steele]

Since I'm going to have to return stuff either way and I've gotten quite chummy with the guy at the UPS Store when I show up to return Amazon purchases, I'm going to do some detective work and investigate this "power draw" theory. I ordered a WD Blue 2TB NVMe:

https://www.amazon.com/gp/product/B09JM8DJNS/

It will come tomorrow morning and I'll put it in the enclosure and see if the dismounts go away. If they do, then the "power draw" theory may be correct and I'll return the WD Black. If it doesn't work... well hell... I'll still return the Black and get a different enclosure for the since I won't be needing whatever extra speed the Black is theoretically capable of.

[Michael Canavan]

Well it wasn't the cable. All of this is kind of pissing me off frankly. Thought I'd be smart and get an enclosure that was recommended by several YouTubers and I was getting awesome speeds, but today I went and booted the Mac Studio and the drive was not on the desktop. I restarted. It wasn't there. I had to unplug and plug the drive and then it appeared on the desktop.

Seems like once it's mounted it seems to be okay. But again... ticks me off.

OK So this is a bit different of an issue than what we've talked about with disks unmounting in use randomly. I would guess that it's a communication problem on start up between the enclosure and the Studio, meaning it's not mounting because Apple and/or Ankmax are not polling and/or publishing correctly to each other. First thing to check next time is if the drive even shows up in Disk Utility, it probably doesn't but if it does, you can mount it from there.

If it's not unmounting during playback, and after initial problems being recognized on startup, then I would keep it, it's likely a tweak by Apple fixes the mount problem in a future version of Monterey like it did for the USBC drive of mine. It's not like that sort of issue has never popped up in the past even with firewire drives for me.

[HCMarkus]

One thing... if an enclosure is not truly a Thunderbolt enclosure, but a USB C enclosure, macOS will not support Trim for the drive it houses.

Not much of an issue for a VI Sample drive, which is largely Read-Only.

[James Steele]

Well it wasn't the cable. All of this is kind of pissing me off frankly. Thought I'd be smart and get an enclosure that was recommended by several YouTubers and I was getting awesome speeds, but today I went and booted the Mac Studio and the drive was not on the desktop. I restarted. It wasn't there. I had to unplug and plug the drive and then it appeared on the desktop.

Seems like once it's mounted it seems to be okay. But again... ticks me off.

OK So this is a bit different of an issue than what we've talked about with disks unmounting in use randomly. I would guess that it's a communication problem on start up between the enclosure and the Studio, meaning it's not mounting because Apple and/or Ankmax are not polling and/or publishing correctly to each other. First thing to check next time is if the drive even shows up in Disk Utility, it probably doesn't but if it does, you can mount it from there.

If it's not unmounting during playback, and after initial problems being recognized on startup, then I would keep it, it's likely a tweak by Apple fixes the mount problem in a future version of Monterey like it did for the USBC drive of mine. It's not like that sort of issue has never popped up in the past even with firewire drives for me.

I've tried mounting it from Disk Utility and it does not show up there. Also, although rare it HAS disappeared after initially being mounted, but that is extremely rare. Maybe only once or twice and I might have been wrong and maybe it wasn't present on boot and I just didn't notice it? When it is present, it seems it's good to go after that.

Right now I'm copying my sample libraries on the the WD Blue 2TB arrive that arrived this morning. One interesting thing that may not have anything to do with anything, but when I first installed the WD Black drive and attached the enclosure, MacOS did not give me the pop up that said there was a drive that needed to be initialized. I had to go find it in Disk Utility. The WD Blue did. May mean nothing at all. Anyway, I'm going to experiment with the WD Blue drive for the next day or two. If it works, I'll reformat the WD Black and return it.

As I'm copying my Sample Libraries over, it does seem that the WD Blue does not heat up as much as the Black. Anyway, it will be an interesting experiment to see if the power draw of the WD Black was indeed contributing to the dismount issue.

[James Steele]

One thing... if an enclosure is not truly a Thunderbolt enclosure, but a USB C enclosure, macOS will not support Trim for the drive it houses.

Not much of an issue for a VI Sample drive, which is largely Read-Only.

That's a good point. Fortunately, I guess I won't be doing lots of writes to this drive after initially installing a new library.

[James Steele]

Just another update. WD Blue drive seems for all practical purposes as fast as the WD Black with Black Magic Test. Only slightly slower in both read and write... but we're talking minuscule difference:

WD Black SN770:
2261.7 MB/s WRITE
2730.7 MB/s READ

WD Blue SN570:
2181.2 MB/s WRITE
2706.9 MB/s READ

So we shall see if the BLUE stays mounted. If not, I need another enclosure, and even then, I think I'll stick with the Blue. I'll go ahead and do a return on the BLACK with Amazon today.

Screen Shot 2022-08-29 at 9.09.21 AM.png (493.41 KiB) Viewed 2493 times

[HCMarkus]

That's because the speed test isn't an extended write. For big writes, the Blue will be a lot slower.

The SN570 isn't as fast as the SN750 or other high-end competitors during sustained write workloads, but that isn't surprising given its four-channel DRAM-less architecture and small SLC cache

[James Steele]

That's because the speed test isn't an extended write. For big writes, the Blue will be a lot slower.

The SN570 isn't as fast as the SN750 or other high-end competitors during sustained write workloads, but that isn't surprising given its four-channel DRAM-less architecture and small SLC cache

Yeah... I know they have different amounts of cache on board and that causes a slow down with large transfers? I read something like that. When I first installed it this morning and copied over 1TB of my sample library to it, it wasn't too bad honestly. It was pretty fast and maybe started slowing down at 700GB or so if I remember correctly.

I'm still trying to figure out what to do. I ordered the Blue as a last ditch effort to test the theory someone posted that the larger power requirements of the Black might be what causes it to dismount occasionally. Although, now since someone brought it up, I'm not *completely* sure if it dismounted or it simply didn't mount upon boot and I didn't notice it until later. Because it seems that once the volume is mounted it's stable.

Full disclosure... just a moment ago, I rebooted and the Blue was not on the desktop. I haven't been able to get it to happen again. I swapped back to the shorter TB3 cable. What's weird is on occasion when I choose "Restart" from the Apple menu, when it boots again it gives me the dialog that the Mac was shut down improperly or had problems. That's rare, too. I think it might be the result of me doing it too quickly after boot, testing to see whether the external mounts, and didn't wait for the EuControl app to establish contact with my control surfaces.

But yeah... I'm going to continue to watch it... but if I get any more times where it doesn't mount when first booting the computer, I have to decide if I can live with that, or I should throw in the towel and get the OWC enclosure as you recommended. Plus, Trim is nice to have. Just got spoiled and liked the idea of the faster transfers, even if it probably doesn't make much difference in real life. I'm thankful Amazon has pretty generous return policies as I feel like I'm sure to make their "watch list."

Again... if I get another "missing on boot" today, I"ll probably just go with OWC and return one of the NVMe drives. Haven't decided yet if it's worth keeping the Black. Probably should them both in the OWC enclosure and then decide from there. I haven't yet erased the Black so it still has my Sample Libraries volume on it, so swapping back and forth and testing will be easy.