Finally there are hotfixes for the annoying CSV IO Paused during the back-up. The issue mostly occurs when multiple CSV VSS Snapshots are initiated. I’ve tested the hotfixes in my test envoirement and the issues seems to be gone now.
Resolves an issue when multiple VSS backups are in progress, the cluster service may crash because of inconsistent state in the CSV VSS provider.
Resolves an issue where unneeded snapshots may not be deleted after a backup is completed. This prevents future backups from failing due to a lack of free space consumed by snapshots.
Component: Hyper-v Integration Services
Increases the time-out to detect the volumes to shadow copy when the Guest OS has multiple volumes.
Component: Rdvgpuinfo.dll / Vmms.exe
Resolves an issue on a Hyper-V cluster where the heartbeat component times out during a long-running snapshot. The snapshot fails and the VM restarts.
The full list of Microsoft Cluster Hotfixes: