I`am testing Veeam Agent for Linux v1.0.0.944 FREE for backup Debian 8.6 "Jessie" server (kernel 3.16.0-4-amd64).
This is FS partition configuration of tested server:

Firstly, I created backup job for backup only MBR, /boot, /root & /var volumes. And created backup files was relatively small
(as You can see, there are not very much of file data on server).

But, recently I added to job /home volume, after that it seems that VA in next run backuped ALL FS blocks, not just data blocks...

/home is 53MB size. Why so much diffrence in size of backup files?