EtreCheck reports a kernel panic today. Also, I can't resintall macOS Monterey.

I tried to reinstall macOS Monterey. I get a screen that shows two volumes: Macintosh HD and Preboot. I click on the HD one, and it says, "The volume cannot be downgraded." Say what? So I can't reinstall macOS if I've done macOS updates? And what about the Preboot volume? What is that? It said 0 KB available. Doesn't sound good!


And about the kernel panic. The machine did freeze strangely. Started with Firefox, I think. I had dozens of tabs open! I suppose that doesn't help things. Never ever got red in the memory pressure graph. The beach ball came on and first spun only over FF, but then spun over everything. The ball often froze and stuttered as it was "trying" to spin. I had seen this before and thought it was from Final Cut Pro 10.6.8. So I downgraded to 10.6.6. Things seemed to stabilize until today.


I was going to reinstall macOS Monterey anyway, as I've had other strange things happen from time to time: Rarely the tabs or header of Finder or the main Mail window would turn red! Often the Time Machine panel suddenly hides itself under everything else. Sometimes it shows strange things. So I thought it's time. But I can't downgrade from 12.6.8 to 12? I have to erase the drive and restore from Time Machine? That'll take many hours! Even First Aid runs take about 3 hours, due to having to check about 2 dozen "snapshots."


Another reason to reinstall the OS was the FCLM (Final Cut Library Manager) app doesn't work right. So I wanted to see if a simple reinstall would fix it before upgrading to Ventura. But given all this, what to do? Should I upgrade to Ventura and hope for no more kernel panics? Bring the Mac in to the local Apple Store for them to diagnose the hardware because of the one or more kernel panics? Erase the disk, reinstall macOS, do all the updates, then restore all my data from Time Machine? It'll likely take many, many hours! (I have two slow TM drives and Backblaze for offsite backing up.)


The machine is barely a year old!


EtreCheck report attached.


macOS 12.6.8 (Monterey)

24" M1 4-port 2021 iMac


TIA!

iMac (M1, 2021)

Posted on Sep 9, 2023 3:09 PM

Reply
37 replies

Sep 17, 2023 10:31 PM in response to betaneptune

Well, I found the cause of my problems with FCLM. If I dismount my LaCie 4TB drive and the new OWC SSD, all works fine. If either drive is mounted, things go crazy and many libraries come up with the wrong size. A third external drive, a WD HDD, works fine. My backup drives are mounted and still everything works fine. It's only if the SSD or the LaCie drive or both are mounted.


I was at first fooled by all the diagnostic log files that end in .fcpbundle. They would show up in FCLM -- dozens of them! So I zipped them up to get them out of the way, and finally figured this out. OK, so what to do? Ditch the new SSD that I bought, in part, for just this very purpose? (The LaCie is very slow, but portable and formatted ExFAT, so I can use it on a PC for file transfers, e.g. I need the SSD to boot my old Mac.) Buy SSDs from various brands until I find one that doesn't cause a problem? Well, at least I finally have something to go on. I will contact the developer (Arctic Whiteness) and maybe they can help.


The files on these troublesome drives work fine in all other apps and utilities, so what could be the problem here?! Stay tuned.


I guess if I get even just one more "kernel panic" I ought to schlep to the Apple Store and let them at it.

Sep 17, 2023 11:56 PM in response to etresoft

etresoft writes: "External drives are great for backups and archives, but they are not really safe and reliable. With newer computers, they are one of the top causes for kernel panics. When we say kernel panics are often caused by "hardware failures", sometimes we mean external hardware."


betaneptune: External hardware causes kernel panics? I've never heard of this with PCs, VAXes running OpenVMS, Stratus, Unix. Why? Why are Macs so susceptible to external devices?


etresoft:

[betaneptune:] A new drive means more money. Esp. for an SSD. I've already spent a ton on this thing and its peripherals.

etresoft: Did you ever hear the story about the oil changes on a BMW?


betaneptune: No.


etresoft: "Apple makes premium products that carry a premium price tag. You didn't take this route to save money."


That's correct. I took this route thinking that being premium products, they wouldn't be so helpless when it comes to external devices that seem to be operating just fine in every other way. And the user interface is getting worse. (Turns out the FCLM problem is due to two particular external drives. The kernel panic(s)? IDK.)


etresoft: It's the internal SSD. The new ones are just crazy fast. Funny how the world works. All of the latest Macs have absurdly fast internal SSDs. They are at least twice as fast as the fastest external SSDs on the market. And you would never be able to find those SSDs. They are ten times as fast an any external SSD that you can actually buy.


And yet, with these new computers, it seems that everyone is just obsessed with using and booting from external drives. They balk at the price tag that Apple charges for the larger SSDs and opt for the smallest one that Apple sells. They figure it is better to spend more money for the fastest possible configuration, then spend a little extra to make it run 10x slower and less reliably, than to spend just a little bit more and just get a bigger

internal SSD.


betaneptune: Well, if the Apple website would tell you that the M1 SSDs run at about 2500 MB / sec and that external SSDs might give you 800 MB / sec., then maybe more people would fork up the extra $400 to get from 1 TB to 2 TB. Only 3 times as fast, BTW.


etresoft:

[betaneptune:] But I recently found out that if the SSD goes bad, you have a brick!

That is true, but it rarely happens.


betaneptune: And "rarely" is still a bit scary. Esp. since you can't boot from an external drive. You need to get a whole new logic board, or maybe even a new computer. Unless you get the $60/yr revolving warranty. That should cover a logic board, I would think. But still a big time sink and a lot of effort! Well, a lot to do, at the very least.


Regarding rebuilding from a clean disk:


Install the OS.

Manually re-install 3rd party apps.

Restore your data from the backup without restoring the apps from the backup.


Is that right?


Sep 18, 2023 4:54 AM in response to betaneptune

betaneptune wrote:

betaneptune: External hardware causes kernel panics? I've never heard of this with PCs, VAXes running OpenVMS, Stratus, Unix. Why?

Then buy a new Vax or Stratus and run Final Cut Pro on that.


Just kidding. 😄 Everyone knows external hard drives for Vaxes are unreliable because it's a huge consumer market and most of those cheapo external drives are only designed and tested for HP-UX.

etresoft: Did you ever hear the story about the oil changes on a BMW?

betaneptune: No.

The story is that they cost $10,000 and require removal of the engine. It's an urban myth, or maybe it is a Porsche or some other expensive car. The moral of the story is that the owners don't mind because they bought the car to spend money and to be seen spending money.

betaneptune: Well, if the Apple website would tell you that the M1 SSDs run at about 2500 MB / sec and that external SSDs might give you 800 MB / sec., then maybe more people would fork up the extra $400 to get from 1 TB to 2 TB. Only 3 times as fast, BTW.

The SSD on modern Macs runs at about 5,000 MB/sec and the best an external SATA SSD can do is 500 MB/sec. With a little research, you can find SSDs that go faster, sometimes much faster. But those are expensive and hard to find.

betaneptune: And "rarely" is still a bit scary.

OK then. It never happens. Not even once. Is that better? Geesh...

Esp. since you can't boot from an external drive.

Of course you can. It's just a hassle. The procedure has been made difficult in an effort to dissuade those people who didn't do that research above.

You need to get a whole new logic board, or maybe even a new computer. Unless you get the $60/yr revolving warranty. That should cover a logic board, I would think. But still a big time sink and a lot of effort! Well, a lot to do, at the very least.

It's not 1983 anyone. If your internal SSD fails, you are absolutely, positively going to need a new logic board.


You didn't mention the time to recover from backup. It's been a long time since I've seen a good 16 page argument about the relative merits of bootable backups for instant recovery from hard drive failure. And you know it's always instantaneous. Ask any hard drive cloning fan and they'll agree - instant.

Regarding rebuilding from a clean disk:

Install the OS.
Manually re-install 3rd party apps.
Restore your data from the backup without restoring the apps from the backup.

Is that right?

No. It's wrong. In this 3 page thread, you happened to say in an aside, "(Turns out the FCLM problem is due to two particular external drives. The kernel panic(s)? IDK.)" [parentheses in original].


If you've made the determination that there is a problem with your external drives, then that's the problem. Disconnect those drives. You don't need to erase the internal or install another operating system. Chances are, it will fix the kernel panics too.

Sep 18, 2023 8:51 AM in response to etresoft

Yeah, there's the walled garden bit. My point was that an expensive machine shouldn't be so vulnerable to disk problems, consumer or otherwise. When there are disk problems on the VAX, everything else still works. Ran a fleet of up to 40 MicroVAXes. Many of them ran on disks in separate StorageWorks towers. A very occasional disk death, and the machine kept running everything else just fine. Ran a trading system on it that we bought from a small company. The head guy told us if you get a "fatal machine check" (I think that's what it's called), you shut down the machine and switch to another one. I suppose that's the equivalent of a kernel panic. Never had one, I don't think. Maybe one. Power supplies occasionally died. It's a very sudden thing, and it's the one device not monitored for errors, but come to think of it, that might not do any good anyway. And man, you had to take almost everything else out to get to the stupid thing. (From 2000 to 2010.)


The Stratus I worked with was fault-tolerant. But it was very expensive. There were three rows of boards: MEM, CPU, IO. Each board was paired with another. If a board died, the other board would keep going and the users wouldn't notice a thing. The Stratus would detect that, call the company automatically, and the next morning there'd be a FedEx package on your desk! The bad board will have a red light. You pull it out, slide the new one in, wait a few seconds for the green light, and you're back in business. And this is done WITHOUT shutting down the machine! The only peripheral was a TLZ07 tape drive. Well, it was built into the machine. And tape drives, . . ., well. And yes, it was very expensive. But just think of it: Pulling out the guts of the CPU or MEM boards, and the thing keeps running like a charm! The users never notice a thing. Incredible.


>----o----<


I thought oil changes at the dealer for BMWs were free. Maybe not.


>----o----<


Happened to me. Had a 3 TB Fusion drive on my last Mac. One day, the machine acted weird (maybe just hesitated for a few seconds) and then died. Got an external drive to boot from, though I had to disconnect my backup drives for it to boot. But I got an external drive to boot from to work. It was a pretty scary "adventure." Oh, on top of that, the macOS had a bug where it wouldn't mount the swapfile. Amazingly, I found some secret commands that would take care of that. And there's even more to the story.


>----o----<


1983? My first PC was actually my parents'. And I think they bought it in 1996. Or do you mean the VAXes? I used VAXes from 1985 to 1991.


>----o----<


I meant, if I ever did have to start from a clean disk, is that the correct procedure.


>----o----<


Well, I will contact Arctic Whiteness about FCLM. If they say I'm SOOL, what am I to do? The 4 TB SSD cost me $900. (Yeah, I bought it just before they dropped it. Bad timing. I can now get more storage for less money.) Even if I bought the M1 Mac with a 2 TB drive, it wouldn't be enough (well, maybe after I do a lot of "cleanup"). And I often had those disks disconnected, so we still don't know what caused the kernel panic. I suppose I could sell it on eBay.


>----o----<


According to the AJA app, I never got 5000 MB / sec. I think the Read figure approached 3000 once. I usually get between 2200 and 2800 or so. The external SSD gets about 800 MB. All this according to the AJA app. Hey, if I were at Apple, you could be **** sure I'd brag about how fast the M1 storage is. Who'd even think to do some research on that when they themselves don't brag about in their own ads on their own website? I did think it would be faster, but Final Cut people told me it doesn't matter: an external drive is enough even for 4K, IIRC. Sounds a little too optimistic, though.


I could go on . . . (^_^(

Sep 18, 2023 5:25 PM in response to etresoft

I wrote: "1983? My first PC was actually my parents'. And I think they bought it

in 1996. Or do you mean the VAXes? I used VAXes from 1985 to 1991. "


Oops. That was my use of VAXes in grad school physics. From 1991 to 1993 I used them as a postdoc. I used them at 3 different jobs since. So the total range is from 1985 thru 2010.


Take 2: Hey, if I were at Apple, you could be dam sure I'd brag about how fast the M1 SSD is.


EtreCheck reports a kernel panic today. Also, I can't resintall macOS Monterey.

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