Time Machine drive slows down logging in and reboots.

[Koloa]

I've noticed this issue for quite a while, but with macOS 12, it's become quite painful.

I have a 12TB external drive on my 2019 MacPro which I use for Time Machine backups.

The backups work fine, but, rebooting my system and logging in takes anywhere between five to ten minutes after providing my credentials - and it's entirely down the 12TB APFS Time Machine volume being mounted by macOS.

Until the TM drive is mounted, apps won't launch and my system is basically "stuck" - I can try to launch things but they just bounce for several minutes until the TM drive is mounted into Finder.

My suspicion has been that the size of the drive, and the number/types of files, means that whatever the fsck process is for the APFS volume means that it just takes a while to do what it needs to do.

If I disconnect the drive and reboot, things are as fast as one would expect.

But with the TM drive connected, macOS has this considerable delay as it mounts the TM drive.

The drive is plugged into a CalDigit TS3 Plus hub, but the experience is the same when plugged directly into the MacPro.

Short of erasing my TM backups (not an option) or moving to SSD (financially unpleasant option), is anyone aware of a way to speed this process up? I'd like to stick with APFS as the filesystem, rather than go backwards to HFS+, but it's getting frustrating waiting upwards of ten minutes every time I restart for the TM drive to mount and my system to become usable.

I've tried reporting this via Feedback Assistant for some time (including for the macOS 12 betas), but, crickets.

Thanks!

 

[maverick100]

It has to do with having APFS on a HD. Over time it will take longer and longer for the HD to mount.
Example: I have two 18tb drives that store a 16tb iTunes library. When they were formatted as APFS the mount time increased over time to over 15 minutes to mount. I erased the drives and formatted as Mac OSX Extended. I have 8 HD's that are 8tb and above; all of them are now formatted as OSX Extended. They all mount with in 15 seconds or less when the iMac starts. I now have TM on 2tb SSD's that are formatted APFS; no issues with anything mounting. All In know is this is what works for me without any mount, unmount, or issues accessing any of the HD or SSD's.

 

[appltech]

Agree with @maverick100 . The problem is inside the APFS.
HFS+ (MacOS Extended) should be on that drive. And it's better to use HDD in proper condition/surrounding for backups (usually it's easier to retrieve/restore files from HDDs)

 

[theorist9]

Also agree with @maverick100. APFS does not like HDD's. Further, if your HDD uses Shinged Magnetic Recording, that will futher acerbate the problem (see: https://bombich.com/kb/ccc6/choosing-backup-drive )

You could switch to HFS+, but then you won't be able to encrypt the backup drive (encryption on Monterey requires APFS). Also, that would require that you move your data onto another 12 TB+ drive while you reformatted your TM drive.

If you don't typically access those older TM backups (i.e., if they're there "just in case"), you could retire your 16 GB drive (ideally to a secure remote location, like a safety deposit box), and continue to backup using, say, a 2 TB SSD.

My suspicion has been that the size of the drive, and the number/types of files, means that whatever the fsck process is for the APFS volume means that it just takes a while to do what it needs to do.

Given that you're understandably frustrated with this, my brain wanted to read this as "whatever the @#&! process is... ";D.

 

[Koloa]

Thanks all - I've ordered an SSD drive to switch to for future backups. I had the feeling the issue was APFS with HDD, just not sure WHY it is so slow. Appreciate the comments!