When a VM has many vDisks across different Datastores
If a VM has many vDisks across different Datastores, and it shows a certain caching operational state in the VM tab of the VirtuCache GUI, then all vDisks assigned to the VM are in that operational state regardless of the caching policy assigned to the Datastores that hold the specific vDisks.
VM level caching policy is derived from the policy of the Datastore where the .vmx file resides (unless overridden by VM specific policy).
VM policy applies to all vdisks uniformly. There is one exception: if a vdisk for the VM is part of a local or uncacheable (e.g. NFS or local disks) datastore, then the VM policy is forced to Write Through (instead of Write Back).