What computer do you have? And what version of macOS are you running?
In terms of "System" size taking up a lot of space (somewhat separate issue of the "Storage" taking a long time to calculate), take a look at the below thread (and others like it, quite a few threads about size of "System" in Storage) - it can be a fairly common issue that users find the "System" taking up a lot more space than they would've thought. One of the things it often is is Time Machine caches - if you don't connect your drive / backup to Time Machine regularly, but you have it enabled, it can take up quite a bit of space. Given you only have 128gb storage (which is on the smaller side for sure), if System takes up a lot, I can see why it would be frustrating.
Hello, hope you are doing good. I went to About This Mac and checked Storage. It says that the System takes up 112 GB of space on my internal SSD. I have a 2017 iMac with interal SSD and the latest High Sierra version. I have very little stuff on my computer. A few big apps but they just take...
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