Hello,
I'm currently using the base model Macbook Air M1 with 8GB ram and 256GB storage. I'm running the latest OS version of Tahoe. In the past few weeks I've started getting low storage warnings and couldn't figure out why because I don't store a lot of files on my computer. I discovered that my System Data is over 110GB according to the Storage section under general in System Settings and I'm not sure what that is or how it became so large. I did some research and it seems that OnyX is a good canddate to help get rid of some of those files in System Data. I already use C Cleaner but it doesn't seem to touch that area at all. Has anyone used OnyX and could point me towards some good tutorials or instructions on how to use it? I'm by no means a tech guru but I can follow directions very well. If anyone has any other recommendations I'm open to suggestions on how to get space back on my hard drive.
Thanks for any help you can give me, I really appreciate it.
Shannon
Comments
apps
Do you have any apps on your Mac that store alot of data?
You could try deleting those apps, than reinstalling them. I have the same computer as you. I love it.
It is not possible
You can boot to recovery and remove stock apps but they are protected, so each update will restore them if you remove them, so there is not much point. Maybe try running the Onyx MacOS tweak utility. It has some cleaning options in it maybe that will get you some breathing room.
https://www.titanium-software.fr/en/onyx.html
Backup and Reset
If tools like Onyx don't help, your only option is to backup your Mac with something like Time Machine, factory reset, and restore from backup. The same procedure needs to be used on an iPhone or iPad. This shouldn't be necessary, but I think there's a bug in all Apple systems that doesn't clear the cached data used by that other category, so it keeps growing until your storage is full. Maybe Apple will fix it one of these days, though who knows given their current culture and unwillingness to prioritize bug fixes over constant innovation through buggy software because they keep rushing absolutely everything.
Agree with Chris
This is pretty much how it's done on all Apple devices. Backup, reset, restore from backup. Things like system cache will be reset to default, of course it will slowly build overtime, as is the way of the Apple. 🫤
Onyx may also be helpful here, as it does a lot to clean your system without having to reset.
HTH.
Edited for typos
Tips on using Onyx?
Like, can we get beyond, "just use Onyx", and into some things you might want to do with it, and why?
Because I gotta tell you, I've got it installed, and I've opened it a couple of times, and I'm honestly wondering why I've got it installed. I haven't felt the need to do one single thing with it.
Partly that's because I don't understand what some of it does, and it keeps telling me "hey be careful you could break things", and partly because people are all "oh it's great for fully uninstalling apps, getting rid of all that stuff than can get left behind". I've yet to see how to do that at all.
I thought about deleting it the other day, so this seems like a great time to figure out whether or not I'm keeping it. What things do I want to clean/do with it, and why? The how is pretty straightforward, I assume, but you know, feel free to mention that too, if you're of a mind.
I'm just wiping mine
I have that model too, baseline configuration but with 16GB of RAM, and am currently in the process of wiping it as it's closing in on 6 years of software updates since the version of macOS Big Sur that it shipped with originally. I did check those stats before wiping it, and system data in particular was consuming 52GB, however I haven't been using it a lot since late-2024, and I'm aware of a bug in which images were being cached to do AI-based content recognition in the background without being deleted afterwards if I recall correctly, so the growing size of system data may result from that problem.
Re: Tips on using Onyx?
There should be a user guide in the Help menu of Onyx. It may, or may not be, inside the Onyx Help option. Been awhile since I've used Onyx, but you should find the guide somewhere within the help menu.
Also, if you're feeling nervous about using the utility, I would advise you just use the default tasks from the Maintenance tab. It will clean up bloat files, such as large caches, that can slow down your Mac's processing output.
HTH.
Edited for typos
Disk Inventory X
I highly recommend installing this app from the official website and once and for all finding out what's taking up your Mac's storage. The app is quite accessible with voiceover, but be prepared for it to become unresponsive when it starts scanning your disk, so you'll need to quit it with command + tab. Once the scan is complete, a window will open with a visual display of your storage usage. Press esc, and the window will disappear, after which you'll be able to see in detail which folders are taking up how much space, sorted by size, descending.
Full restore is underrated
This can do so much beyond storage, weird bugs (including but not limitted to voiceover) can be silently patched, overall performance gets better, and on windows especially now if I don't wipe everything after a year I start to feel the pain.