The new on-disk format
The first generation of VSAN used the VMFS-L (v1) filesystem, which is a modified version of VMFS. With the second generation of VSAN, there is a new on-disk format called VSAN File System (VSANFS). This new filesystem significantly enhances snapshot scalability and clone management support. VSAN 6.0 supports both the v1 and v2 filesystem types. However, to uncover the newer features and enhancements, the filesystem from a vSphere 5.5 deployment needs to be upgraded.
If the cluster is created from scratch on vSphere 6.0, the new filesystem is automatically used.
Snapshot enhancements
As an outcome of leveraging the new on-disk format, snapshot handling at a filesystem level has been modified. The new snapshot format with VSAN 6.0 is vsanSparse. This effectively replaces vmfsSparse, which has certain basic limitations in terms of performance and scalability. While there are no user-visible manifestations of vsanSparse, administrators can be assured that there is a relative...
