ChrisGundryCEGA wrote:My thinking being that the size of the files should match the size of the used space. The ReFS and spaceless full backups should actually mean that the space used at the disk level shows less space used than the size of the files shows.
But as we don't have any spaceless full backups yet, the space should just match and be the same, within a small margin to account for the 64k block size and a file that is less than 64k taking up a full 64k. But there is very little data on this volume at present.
Currently it now shows 79GB used in file properties and the disk properties shows 310GB used!
Treesize also only shows 79GB being used.
Treesize also shows 42.6TB free of 42.9TB so again 300GB usage, but not in the Veeam files...??
Did you check the volume immediately after you formatted it? ReFS sets aside a significant amount of space during format, by my observation around one-half of 1% of the size of the volume as reserved space, but it doesn't seem to be completely linear so that's just an estimate. With a 47TB disk that would be almost 250GB shown as used immediately after formatting. 4K clusters set aside more space than 64K clusters, the gap widens as the volume size goes up.