Part of: System Data on Mac: what is inside and how to reduce it safely (System Data)
Two newer sources of System Data confuse people: the files Apple Intelligence needs, and the cache a background service called mediaanalysisd keeps. Neither is a leftover to hunt down. This guide shows where they live, how to check their size and why you should usually leave them to macOS.
What each one is
Apple Intelligence features rely on models, which are large files macOS downloads when you turn the features on. macOS manages where they are stored and when they are updated. Their size depends on your macOS version and on which features you enabled, and Apple can change it. We do not state a figure, because we cannot verify one for your Mac.
mediaanalysisd is a background service that analyses your photos and media, for example so you can search by what is in a photo. It stores the results in a cache in your Library.
How to check the cache size
The cache lives in a container folder in your Library. This read-only command shows its size:
du -sh ~/Library/Containers/com.apple.mediaanalysisdOn the Mac used for this article it showed about 636 MB on 2026-10-05. That is one example, and it will differ on your Mac. A Mac with a large photo library can have a larger cache.
For the bigger picture, open Apple menu > System Settings > General > Storage. The models themselves are system data, and the Storage view will not itemise them for you.
Why you should usually leave them
The cache is rebuilt if it goes missing, but then macOS analyses your photos again, using CPU and battery for a while. You save space for a short time and pay for it later. Because the model files are managed by macOS, there is no folder you should delete by hand.
If you do not use Apple Intelligence, the supported way to stop the models is to turn the feature off in System Settings. We have not tested how fast that releases space on every macOS version, so do not expect an instant change.
Safe, Risky, Never
Safe
- Checking the size with
du -shas above. - Turning off features you do not use, through System Settings.
- Leaving everything to macOS.
Risky
- Deleting the
mediaanalysisdcache. It is a cache, but photo search is slower until it is rebuilt. - Turning features off and expecting space back at once.
Never
- Touching your Photos library package to save space. It is protected for good reason, and DiskJoy treats it as protected too.
- Deleting system model folders by hand.
What breaks
If the cache is removed, nothing is lost, but analysis starts again, and search by photo content is incomplete until it finishes. If you disable Apple Intelligence, its features are unavailable until you enable them again.
Why it feels like space “disappeared”
You turn a feature on, and your free space drops by a visible amount. That is the model download. Because it happens in the background, you may not connect the two events. The space then sits in a system-managed place, so it can show up under System Data or under a similar category, depending on your macOS version.
This is not a leak. It is the cost of running the feature on your Mac instead of in the cloud. If you rarely use the feature, switching it off is a fair choice, and you can switch it on again later.
How to keep an eye on it
Note your free space before you enable a new feature, using df -h /System/Volumes/Data, and again a day later. The difference is a fair estimate of what the feature cost on your Mac. It is more honest than any number we could print, because it is your own.
You can do the same for the cache:
du -sh ~/Library/Containers/com.apple.mediaanalysisdIf the figure grows steadily over weeks, that usually reflects a growing photo library, not a fault.
What this means for a small disk
On a Mac with a small disk, every few gigabytes matter. Before you enable a new feature, check that you have comfortable free space, and remember that macOS needs working room for updates. If space is tight, the gains from disabling features you do not use may be larger than the gains from clearing caches.
For the general approach to finding large things, read the System Data guide. For another background process that grows with your files, see the Spotlight index guide. If the Storage figures look odd, the purgeable space guide explains why, and System Data on Tahoe covers the newer release. Photos library size is a separate topic: why the Photos library is so big.
Check the big picture
DiskJoy is our product. Its scan is read-only today: it removes nothing, reports allocated bytes with a lower-bound reclaimable estimate, and it leaves the Photos library alone. To see where your space goes, run the scan.
Frequently asked questions
How much storage does Apple Intelligence use on a Mac?
It depends on the macOS version and which features are on, and Apple can change it. We do not give a fixed figure. Check your own Mac with the storage settings.
What is mediaanalysisd?
It is a background macOS service that analyses photos and media, for example for search and recognition. It keeps a cache of its results in your Library.
Can I delete the mediaanalysisd cache?
It is a cache, so macOS can rebuild it, but analysis then runs again. The data is part of how Photos search works, so removing it is a low-reward step. Do not touch your Photos library itself.