Really ? 66Gb of Biome - something must be wrong

I am trying to clean up my internal SSD of M1 Mac Mini. I ran DaisyDisk and found this folder of 66GB

I checked on the Internet what is Biome and found this informative (but I cannot understand all) article from the Electric Light Company

The TL;DR of the article for me is that

As a last-ditch measure, deleting the contents of the Biome folder shouldn’t result in any data loss.

Before I go ahead , I want to ask the wise people here, do you have the same issue and have you delete the Biome folder?

Mine is only 344MB - but from reading the article, that’s not surprising.
I don’t use Siri on the mac nor it’s suggestions, not sure they even come up wtih Alfred.

yeah, that is about the right size. I digged in deeper into Daisydisk under Biome folder and found major of the storage is taken up by a folder called Tomestone (what a great name). I googled what this is and found this discussion . The person posting the discussion have 150G in the folder !!!

I run the Apple Mail app all the time on this M1 Mac as the SpamSieve robot. Not sure this is related.

something has happened on 24 JAN 23 or the issue was corrected when I rebooted , before 24 Jan, each file is 16.8 MB but was created at random times. After 24 Jan , a 1Mb file is created almost every minute

very weird

If you look closer, you see that also before that change towards 1MB file size, the interval was partly even several times a minute.
So there is no change within the interval, as far as it is visible on the picture.

yes, for this screenshot but this shows a different story, still do not know why these files are generated

Also not really, there are sometimes several files a minute, and sometimes 30-45 Minutes between them. I assume, that the computer was switched off between 12:12 and 05:16 (or somewhere in between)?

Have you tried to open one of the files, to see what it contains?

I don’t have this on my M1 MBAir (Ventura 13.2) - nothing in ~/Library/Biome (folder doesn’t even exist).

Both on my MacBook Air M1 and the Mac Mini M2 those biome folders are empty (they do exist and there are subfolders that are empty, too). My Mac Mini does not run 24/7, it is being shut down when not in use. My MacBook Air is sleeping when not in use (closed lid).

After having read Howard Oakley’s article on his The Eclectic Light Company blog which was mentioned above:

  • It is a MacOS daemon that does stuff regarding suggestions, collecting data from relevant apps.
  • Some data being stored there is encrypted in order to protect potentially private material, so there is not much sense in looking into those files.
  • Tombstone is a folder that contains expired files that is “weeded” periodically.
  • Sometimes things get out of hand for unknown reasons and the folder gets huge: restarting your Mac can fix the issue.
  • “Deleting the contents of the Biome folder shouldn’t result in any data loss.”
  • “It’s almost completely hidden from the user, and only now starting to become accessible to third-party developers.”

Time will tell what Apple is cooking here…

More on that:

Long story short: if you have no issues, the biome folder can be ignored. If Biome is filling up your drive, restarting the Mac might be a good idea. If that does not help, deleting the contents of the Biome folder manually should not do any harm - and you should be fine.

If it keeps filling up your hard drive even after all that, there is something weird going on in your MacOS installation. Could it be an app misbehaving causing this daemon writing data to the drive like crazy? I have no idea. If even Howard Oakley does not know exactly what is going on, I for sure do not, either.

It may be interesting doing some debugging with a fresh, new user: does it happen there, too?

If nothing helps, a fresh MacOS install may be in order. But first things first: restarting, maybe deleting Biome’s contents afterwards could already do the trick. And debugging further…


Or a macOS subsystem gone totally rogue, perhaps? I think I’d suggest the “nuke & pave” approach.

For the record, my Biome folder takes 215M.

Yes, it very well could be that way, too.

A nuke & pave always helps, but it can be a pain. I have done so last year because of iCloud issues and I do not regret it, but… it took me weeks until my Mac was in a state again I wanted it to be in. :slight_smile:

Maybe, a “nuke and pave” of just the Biome contents like Howard Oakley has suggested in his blog post already can resolve the issue.

Before a “Nuke & Pave”, I would almost every time recommend to have a look into Disk Utility first, and to give “First Aid” a try.
Often it fixes weird problems like that very well…