macOS Sierra, system size is 180+ GB! [duplicate]

macos storage

Download Diskkeeper and analyze your hard drive.

OmniDiskSweeper will show you the files on your drive, in descending order by size, and letting you decide what to do with them. Delete away, but exercise caution.

Omnidiskkeeper will show detail of space usage:
Select System and start cleaning. enter image description here

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