How to retrieve unused space from Ubuntu VM using vmware player

Steps to retrieve unused space

Defragment (no need to un/remount anything). Ignore any errors. Some files like symlinks and device files can’t be defragmented.
```
sudo e4defrag /
```
Zero-fill all unused space so VMware knows it’s indeed unused:
```
dd if=/dev/zero of=wipefile bs=1M; sync; rm wipefile
```
Run the shrink operation:
```
sudo vmware-toolbox-cmd disk shrinkonly
```