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

[FNH15]

That doesn’t sound promising. Pretty sure that a normal system data cache is below 20Gb, ideally below 10 GB. But if it’s not increasing after hitting that 29 GB then that’s at least a good sign.

After beta 2, down to 27GB. It’s possible it’s larger due to beta logging.

 

[yawitz]

So glad I found this thread! I'm having what looks to be the exact same problem as @gooutside. Until now, web searches, and a visit to the Apple Store, all led to the "recommended" solution: to reset and restore from a backup. That fixed the problem at first, but just as reported here, System Data has been growing by ~2-8 GB/day. I tried a variety of offloading and/or deleting suspect apps, with no permanent result.

I am with @gooutside, in that I'm not willing to discard years of phone usage and return to a pristine, day-1 state; this should be fixed on Apple's end.

The detective work by @dferdo04 (and followed up by @gooutside) is most appreciated, and lines up with my own experience, pointing to the icon cache as a suspect. I have many app folders on my phone (organizing hundreds of apps); I am seeing the icon redraw bug reported elsewhere (i.e. single apps and app folders all needing to redraw from time to time), and this seems to correlate with a jump of 1-2GB of System Data.

I'll report back here if I learn anything new, but I believe @gooutside has this covered. I'm looking forward to a fix in iOS 27.

 

[Rydawg96]

So I hear the public beta of iOS 27 just dropped. For those who have been using the prior betas of 27 on their devices that had system data issues with iOS 26 (devices which were not erased and tested clean instead of restoring from backup), what’s the verdict? Same system data issues, or finally resolved?

 

[FNH15]

So I hear the public beta of iOS 27 just dropped. For those who have been using the prior betas of 27 on their devices that had system data issues with iOS 26 (devices which were not erased and tested clean instead of restoring from backup), what’s the verdict? Same system data issues, or finally resolved?

Have been using iOS 27 since the first beta. System Data has been consistently around 24GB.

 

[yawitz]

OK, I think I have an iOS 26 workaround. Based on the hypothesis discussed here, I used the Edit Pages feature to “hide” the home screens that contained many app folders, leaving only a couple of screens with single apps and a single folder visible. (I can still access those apps via the App Library.) Today, about 12 hours later, with no other changes to my phone usage, my System Memory dropped from 85GB to 20GB, and it seems to be relatively stable. (It’s risen to 21.5GB after a couple of hours, but it’s still well within a reasonable amount.)

I’ll check this over the course of the day, but until the issue is resolved (hopefully in iOS 27), this may be a good temporary fix.

 

[yawitz]

Well, that didn't last long. I'm sorry to report that after 12 hours, my System Memory jumped back from 20GB to 90GB, seemingly making up for lost time after the previous day's drop. So I'm back to losing 2-5GB per day again.

I tried un-hiding the home screens with many apps/folders for the rest of the day, then re-hiding them, hoping to reproduce the drop in System Data consumption, but the earlier improvement did not occur.

 

[Rydawg96]

Is it just me, or does it seem like the system data bug was finally fixed in 26.6? It’s been at least a week now and my system data is only at 6.86 GB, and it’s usually way higher than this after an update by now. And last time I checked after this update, it was at 14Gb, so it seems like my system data is going down after an update for a change. And keep in mind, I haven’t don’t a system restore on this iPhone since 26.2, the last update that caused my iPhone to hang on updating, and considering that all other updates between 26.2 and 26.5 had the system data bloat as high as 60-70 GB before I had a chance to update, this is a good sign the bug is finally fixed. Fingers crossed it stays this way.

 

[yawitz]

Is it just me, or does it seem like the system data bug was finally fixed in 26.6? It’s been at least a week now and my system data is only at 6.86 GB, and it’s usually way higher than this after an update by now. And last time I checked after this update, it was at 14Gb, so it seems like my system data is going down after an update for a change. And keep in mind, I haven’t don’t a system restore on this iPhone since 26.2, the last update that caused my iPhone to hang on updating, and considering that all other updates between 26.2 and 26.5 had the system data bloat as high as 60-70 GB before I had a chance to update, this is a good sign the bug is finally fixed. Fingers crossed it stays this way. View attachment 2653389

It seems to have been fixed for me as well. My number is higher (~30GB), but stable for weeks. (It's a 512GB phone, loaded with apps.) FWIW, my phone was bricked when I had tried the update (requiring a full reset to factory state and restore from backup), but all has been good since then.

 

[theuptowner]

It seems to have been fixed for me as well. My number is higher (~30GB), but stable for weeks. (It's a 512GB phone, loaded with apps.) FWIW, my phone was bricked when I had tried the update (requiring a full reset to factory state and restore from backup), but all has been good since then.

I have had the exact same issues (including the bricking), and iOS 26.6 fixed them all for me.

 

[Helmsley]

Only just come across this thread, so I've checked mine out of interest (iPhone 15 running iOS 26.6.1, never been reset or had a clean install).