After setting up the Catalina and Xcode, vmdk file size in windows is over 70GB, while actually occupied space in Catalina shows around 46GB. By using the defragment and compact tools of VMWare, vmdk fle size in windows is still over 70GB.

So I tried below. Works great!

1. copy the vmdk file as a backup and source volume (mentioned later)
2. add #1 to the VM as a new SATA disk in VM setting
3. create a new SATA disk in VM setting, 100GB
4. boot the VM
5. in Catalina, run disk utility
6. Select ‘Restore’ from disk #1, be careful since the volumes’ name might be same in Disk Utility.

After doing so, the newly created VM disk onlyoccupied around 50GB