Hi,
We have 6 Windows Server 2012R2 VM wich do the same, generated high amount of dirty bitmap end of the day on daily backups.
Example:
DC 01 generates 41 GB of 61 GB,
File server generates 350 GB of 850 GB (Shared Folder, WS2012R2 deduplacation active)
File server generates 1000 GB of 1500...