When attempting a vRanger backup or restore, it is observed that the throughput is consistently low.
A possible cause of this is high disk latency (DAVG/cmd) on the virtual machine datastores.
You can investigate if this is the issue by starting a putty session to the host on which the VM's reside and running ESXTOP
The following VMware knowledgebase article, describes how to do this in detail: kb.vmware.com/kb/1008205
