TM vs WhatSize and the Finder

Question

I have been trying to find a way to look at the various backup folders to see how big they really are. No luck so far.
The hard links that TM uses are fooling both WhatSize (v10.4.0, released today) and the Finder. BTW, earlier versions of WhatSize will die before it finishes measuring my backup disk.
WhatSize says that there is 6.23 TB of data on my 750 G (698.5 formatted) disk. It says that each of the 31 actual backup folders is about 208 GB (they vary a little).
The Finder, when told to calculate sizes and Nudged to actually do it, does the same thing. Each folder is shown as the total size of the disk at the time it was backed up.
This is due to the hard links. TM uses hard links to represent files and folders that have not changed. Therefore, if a particular file has never changed, it is only on the disk once, but it is pointed to as many times as there are backup folders. Each hard link goes directly back to the original file and it gets counted again for every backup folder. Hard links are designed to look identical to the original file and they sure do. The actual source file won't go away until EVERY hard link that points to it is deleted. The first instance of a file entry in a directory is actually a hard link. Each hard link CAN have a different name too but it will still point back to it's source file. Each hard link carries equal weight to the file system.
- gws

Answer 1

WhatSize 10.4.0 reports the virtual size
Finder won't reliably measure the size