I had been struggling with this issue for a long time. No matter what I tried—clearing cache, deleting unnecessary files, following every trick on YouTube and forums—the System Data just wouldn’t shrink. Sure, I managed to free up a little space here and there, but the core problem remained.
It felt like my Mac was hoarding space for no reason. 120GB of precious storage was stuck under “System Data,” and I couldn’t figure out why. I was running out of options, so I turned to AI and asked for every possible solution.
Then, AI suggested something I hadn't seen before:
Run this command in Terminal:
sudo mdutil -a -i off
I had nothing to lose, so I ran it… and BOOM! My used storage dropped from 80% to 40% in an instant. That stubborn 120GB of system data shrank to just 35GB!
So, what does this command do?
It disables Spotlight indexing across all drives. macOS uses Spotlight to keep track of your files, but over time, its database can grow ridiculously large. By turning it off, I freed up a massive chunk of storage. If you don’t rely heavily on Spotlight search, this is a game-changer.
If you ever want to turn it back on, just run:
sudo mdutil -a -i on
For me, this was the magical fix I had been looking for. Hope it helps you too! 🚀
