It is apfs snapshots for Time Machine. Exclude your git folders from time machine and the perf of everything should improve.

APFS snapshots for Time Machine suck so much. They take up a ton of disk space and TM's GUI is horrible, it will just sit there syncing for forever with nonsensical time estimates. Then, once it finishes syncing, it will _eventually_ clean up those old snapshots. I've considered dropping TM completely because of this and sticking with just Backblaze and CarbonCopyCloner instead.

If I exclude my git directories (one of the most important things on my computer) then I really don't see the point of using TM at all with the other backups I do regularly.

Genuinely curious... why do you see the need to back up git?

Even if I don't want to push to a server, I use a different disk or USB as an additional remote in git and push to that. Although I do that only for financial data, so only done once a month so it's not too big a hassle.

I have had good experience with Arq backup 7

Despite its apparent opaqueness, TM is reasonably transparent for the everyday Mac user

Yeah TM has its shortcomings. I went with Arq (non-affiliated) instead.

Adding a folder to the Time Machine exclusion unfortunately does not exclude it from the local snapshots, it only removes it from the copy it does to the TimeMachine destination volume.

From https://eclecticlight.co/2025/10/02/why-did-that-macos-upgra...

> Backup utilities including Time Machine normally make a snapshot with each backup, and retain them for 24 hours, following which they’re automatically deleted. As snapshots can’t exclude folders in the way that Time Machine can in its backups, if you’ve been working with a couple of 100 GB VMs then they will be retained in snapshots even though you probably exclude them from being backed up.

I exclude node_modules and other dependency folders from backups, but projects are pretty much a key thing I want. I might have online repos, but there's usually local branches I want backed up automatically.

I’m very serious and not kidding but where are these settings? I always thought that Time Machine just eats my Computer whole and in chunks with no option for any customization.

Go to Time Machine Settings, click the very prominent Options button, and add things to the "Exclude from Backups" list.

It still do no have the `.git` or any other pattern for that matter. I do can add a while folder, though.

Are you able to wildcard excludes?