System Data Overflow Bug - storage full with 170GB of undeletable data!

[harkon]

Hmm. Last week something strange happened. I always had this problem. On my 512GB iP17PM I had about 20GB of system data after restoring the phone from my iCloud backup. System data startet to grow and reached up to about 50 GB. I have a lot of apps installed an a rather large offline music library. After the update to 26.2 the system data went back to about 20GB and startet to grow again. I was sure that I had to live with this problem. But: all of a sudden from one day to another about a week ago I checked system data after waking up and was surprised to see that it decreased to about 11GB!!! Since then it is stable between 11 and 13 GB. I really don’t know what changed. A lot of app updates of course. But I cant really make a connection between a specific app update and the decrease in system data. I didn’t change anything else. The same offline music. Same amount of photos. Same apps. It stays on the low level even after hard reset.

 

[harkon]

Hot-diggity-dog! I was able to get the storage logs, and ran a script just to analyze the private_var-dev_disk1s2.fslisting file. It revealed that, yes, I also have an enormous directory: /private/var/containers/Shared/SystemGroup/systemgroup.com.apple.lsd.iconscache . It's 50.2 GB. Deeper inside that directory are 161,000+ files inside, just a few MB each, with names like this: F5C1530A-055E-3CA0-AA9B-E0C05AED3709.isdata.

And that's not all – I found an old diagnostic I ran from November, ran the script and found that it, also, had an out-of-control icon cache.

So – it looks like there's some kind of dumb crap going on with this icon cache. I tint my icons red when in Sleep mode. I might try turning this off, for now.

But – I think we're on to something with this icon cache. Any ideas on what we can do with this?

This is what I always thought. My system data always increased after I experienced the icon redraw bug. It felt like the icons were somehow cached but always added on top of the old cache. All of a sudden the problem disappeared for me. I can’t figure out why.

 

[gooutside]

An update: as expected, my phone did it again! It's been less than a month and, sure enough, the System Data has plugged up every single bit of available space – like a pathological, mindless moron – and a review of the iOS Storage Logs shows that, once again, it's related to /private/var/containers/Shared/SystemGroup/systemgroup.com.apple.lsd.iconscache.

I tried to stem this behavior by preventing icon tinting but – that didn't do anything, apparently.

Once again, I'm going to have to wipe and re-install everything on my phone, and – once again – I will file another bug report about this repeated issue with Apple – an issue that is entirely and completely outside my control to resolve.

 

[seaweed_coast]

An update: as expected, my phone did it again! It's been less than a month and, sure enough, the System Data has plugged up every single bit of available space – like a pathological, mindless moron – and a review of the iOS Storage Logs shows that, once again, it's related to /private/var/containers/Shared/SystemGroup/systemgroup.com.apple.lsd.iconscache.

I tried to stem this behavior by preventing icon tinting but – that didn't do anything, apparently.

Once again, I'm going to have to wipe and re-install everything on my phone, and – once again – I will file another bug report about this repeated issue with Apple – an issue that is entirely and completely outside my control to resolve.

Hi, does iOS 26.2.1 fix this issue?

 

[Diopter]

I've heard that it isn't fixed with watchOS 26.2.1 at least, so it seems unlikely to be fixed in iOS 26.2.1 either.

When people update to iOS 26.3 next week I'll be keen to hear if it fixes it for anyone.

 

[Rydawg96]

So I found out that when I update iOS, it actually manages to clear out the system data without needing to do a system restore. The unfortunate thing is you will likely need to use the beta releases, as the final releases aren’t released quickly enough to clear the system data before it gets to full. And while you are testing the beta versions, make sure to report it to Apple in the feedback app every time your system data consumes another 10Gb of data, and with each beta release you install. That way, it will get Apple to make a permanent fix once and for all, as I consider this just a temporary fix. I am currently at 33.08 GB system data without 26.3 beta 3, thought with beta 1 it reached up to 60GB before I installed beta 2.

 

[dcmaccam]

So I found out that when I update iOS, it actually manages to clear out the system data without needing to do a system restore. The unfortunate thing is you will likely need to use the beta releases, as the final releases aren’t released quickly enough to clear the system data before it gets to full. And while you are testing the beta versions, make sure to report it to Apple in the feedback app every time your system data consumes another 10Gb of data, and with each beta release you install. That way, it will get Apple to make a permanent fix once and for all, as I consider this just a temporary fix. I am currently at 33.08 GB system data without 26.3 beta 3, thought with beta 1 it reached up to 60GB before I installed beta 2.

This seems a strange problem. On my iPhone 16 Pro my System storage is currently 2.9 Gb and doesn’t vary much. Note, I am not signed into iCloud which I don’t use for anything.

 

[TumbleDryer]

I have an issue with the icon cache in Tahoe. My external drives all appear in the Finder sidebar with Adobe CC icons instead of the relevant disk icon. I keep clearing the cache but eventually it comes back. Now MacOS and iOS are becoming a hideous mix of each other maybe our problems are related?! The system constantly rewriting/readdressing icons? Either way Apples quality these days is severely lacking.

 

[gooutside]

Hi, does iOS 26.2.1 fix this issue?

Hello! No, it did not. Neither did 26.3. Nothing has – every release, every beta, all of it: it obsessively builds, over and over again, the icon cache. Like a mindless, pathological, relentless, obsessive freak.

I am presently resetting and restoring my phone. Nothing fixes this. I've reported it to Apple multiple times – they do not seem to care. At all.

 

[orbital~debris]

The icon cache aspect reminds me of something I've noticed on recent iOS versions: when opening Settings app, all of the icons gradually load – instead of being just… there.

Is anyone else seeing that behaviour? If so there may be a larger issue with icon caching and redraws (perhaps caused by all the variants for different icon modes that iOS now has).

 

[Rydawg96]

Currently in the process of installing iOS 26.3.1, which did not have a beta release. Did mention bug fixes but didn’t mention what it fixed. Fingers crossed this one may fix the icon cache bug, or I will be beta testing 26.4 to hammer Apple’s developers to fix it in beta again. System data is at 70GB with 107 GB free, hopefully the update doesn’t crash with this much full unlike when the system data took all the remaining space on the phone.

 

[Rydawg96]

Got 26.3.1 installed, all that system data has now shrunk down. Funny how everyday use doesn’t clear itself, but a simple software update clears out most of the cache without needing to do a system restore. Will keep you updated weather the bug is gone or not in 26.3.1

 

[seaweed_coast]

Got 26.3.1 installed, all that system data has now shrunk down. Funny how everyday use doesn’t clear itself, but a simple software update clears out most of the cache without needing to do a system restore. Will keep you updated weather the bug is gone or not in 26.3.1 View attachment 2610099

Do you have this upgrade issue?

Getting stuck on Apple screen with progress bar every time I do an update

I'm wondering if this is only happening to me since I haven't been able to find anything about others having this issue. With several versions of the iOS 26 beta, whenever I install an update, my 16 Pro Max will install the update and then get stuck on the Apple with progress bar screen with a...

forums.macrumors.com

How much System Data is before your upgrading?

 

[macguy167]

I have a major issue with my iPhone, and I have found no way possible to fix it! All of the sudden, my storage keeps going full, and there is no way to get any free data whatsoever because of what’s actually consuming it.

I love how Apple is so unresponsive on tough support issues!

Always the same lame answer, but no real solutions!

Timmy Cook looking at you! Aren’t you retired yet?!

 

[gooutside]

Got 26.3.1 installed, all that system data has now shrunk down. Funny how everyday use doesn’t clear itself, but a simple software update clears out most of the cache without needing to do a system restore. Will keep you updated weather the bug is gone or not in 26.3.1

After 26.3.1, my "System Data" also shrunk – and I would love to come back here in 2 months and tell you that the problem went away – but I'm not holding my breath.

 

[dcmaccam]

I don't not connect to iCloud for anything and have never had any problem with excessive system data. Do the people that have problems use iCloud?

My iPhone 16 Pro has 3.39 Gb of System Data
My iPad mini 6 has 12.4 Gb of System Data

Neither of them has varied much from these figures.

 

[seaweed_coast]

I don't not connect to iCloud for anything and have never had any problem with excessive system data. Do the people that have problems use iCloud?

My iPhone 16 Pro has 3.39 Gb of System Data
My iPad mini 6 has 12.4 Gb of System Data

Neither of them has varied much from these figures.

Currently, the conditions under which this issue occurs are not clear. It may not affect all users. What we do know is that a service related to icons keeps writing cache files to System Data continuously without deleting them.

I use iCloud and have about 500–600 apps installed. It’s possible that having too many apps installed, or that some apps have problematic icons, is causing the icon-related service to behave abnormally.

How many apps do you have installed? I have tried deleting many apps and keeping only a little over 300, and I’m currently observing whether the issue still occurs.

 

[dcmaccam]

Currently, the conditions under which this issue occurs are not clear. It may not affect all users. What we do know is that a service related to icons keeps writing cache files to System Data continuously without deleting them.

I use iCloud and have about 500–600 apps installed. It’s possible that having too many apps installed, or that some apps have problematic icons, is causing the icon-related service to behave abnormally.

How many apps do you have installed? I have tried deleting many apps and keeping only a little over 300, and I’m currently observing whether the issue still occurs.

I have only 90 Apps installed including the default Apps

 

[seaweed_coast]

I have only 90 Apps installed including the default Apps

Do you mean that you only have about 90 apps installed, yet you’re still experiencing the issue where system cache storage keeps increasing?
Would it be convenient for you to list the third-party apps you have installed?

 

[Rydawg96]

gonna be updating from 26.3.1 today to 26.4. Current system data is 52.96, which is interesting as it was over 60 GB yesterday so that’s a bit of shrinkage there

 

[dcmaccam]

Do you mean that you only have about 90 apps installed, yet you’re still experiencing the issue where system cache storage keeps increasing?
Would it be convenient for you to list the third-party apps you have installed?

Sorry, I have 90 Apps and I have never had a problem with System Data storage increasing

 

[iOSBry]

gonna be updating from 26.3.1 today to 26.4. Current system data is 52.96, which is interesting as it was over 60 GB yesterday so that’s a bit of shrinkage there View attachment 2616389

How’d it go?

 

[gooutside]

I've upgraded to iOS 26.4 and I can confirm the bug still exists. The /private/var/containers/Shared/SystemGroup/systemgroup.com.apple.lsd.iconscache directory keeps filling up with dozens and dozens of gigabytes of icon cache data, relentlessly and obsessive-compulsively. I have filled out several bug reports and I'll add yet another one for Apple to ignore.

 

[Diopter]

As a tip, people reporting this should share their feedback IDs here and reference them in each other's feedbacks so that Apple's feedback triaging team can see multiple people are reporting the same issue. It does help it get more attention.