Getting my system data back

May 09, 2024

Sometime this autumn, my work Macbook pro (a 14-inch 2021 M1 pro) developed a strange storage issue. Basically, the section "system data" in system settings occupied an extra 220 or so gigabytes of space, and it never corrected itself no matter the cleaning and disk utility repairs I did. One more person in the Kodsnack Slack had the same issue, and there were a few reports of similar problems in random forums online, but no explanations or solutions.

The problem seemed to develop during one particular day. I for some reason noticed free space getting lower and lower, finally getting system warnings about being out of space, then restarting and immediately needing to throw stuff away to have any space left at all. Deleting things did free up space, but only the usual amount. The "dead" space in system data stayed occupied no matter what I did. Everything kept working just fine otherwise however, I never had any problem with my actual data (which was of course a great relief).

So, last night I finally sat down and did a proper nuke and pave:

First, I did a complete Superduper backup to a external SSD. It truly is wonderful to live here in the future, where you can have external storage this ludicrously fast to work against. 220 or so gigabytes went by in what felt like no time at all. This also confirmed that my actual data was in good order - the backup was exactly the amount which should be on the system.

Then, I rebooted into recovery mode, used Disk utility to reformat the drive, and reinstalled everything.

This process felt a little fuzzy, but I think it was mainly about me trying to do things in the wrong order, and also secondarily being on a somewhat slow network when the installer was getting online to activate and possibly download data for the install.

The main confusion was that I thought I would want to boot off of the backup on the external drive and use Superduper to restore the backup onto the internal drive. These days, booting from external drives is disabled by default, requiring a trip to a startup security utility in order to allow it. And that part just didn't seem to work when you were in the inbetween state of not actually having a system set up on the computer's internal drive.

It would probably have been solvable, but it turned out to be unnecessary in any case. What I did instead was just pick the option to reinstall Macos normally. Once the basic installation is finished, you get the option of importing data from a backup or other Mac, and there you can pick the Superduper backup on an external drive and just go. Perfect!

A reboot or two later, everything is back in the right places just the way I left it. All I need to do now is click through a lot of dialogs to let things run which I have already allowed in the past, and wait for some indexing to finish.

Macbook pro reappreciation

As I was running through the process, I moved the Macbook pro to a different room. It felt nice to leave it in its own spot, with power connected and the external SSD in a spot with no risk of accidental cable pulls or other incidents. This very minor move somehow made me rediscover just how nice that machine really is. So solid, so compact and powerful, and such a beautiful screen! How come I never notice that the same way even though I work on it day in and day out?

No matter the reason, it is great when I do notice. Computers these days are so awesome, even when they come up on three years old.