Comment 3 for bug 902163

The filesystem needs some space for its data structures. This may account for the difference in used space (i.e. if the filesystem is resized, less space is needed to keep track of things).

One way to ascertain it, if possible, would be to re-resize the disk to the previous value (i.e. enlarge it), and seeing whether the "used space" count goes back to what you had before.

What do other tools (for instance, "du -h" in a terminal) say about the used space?

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