Hey everyone. Quick question regarding vSphere clone tasks on a running VM as it relates to performance. First some context..
We've got 4 hosts all connected with a dual port 10Gb SFP+ interface each up to our switching infrastructure. These two ports are used to connect to two different SSD based SAN devices using ISCSI MPIO. They are also used for VM standard network connectivity up to the rest of our network. Because these two ports on each host are used for everything, I made it a point to throttle traffic on the vMotion vmk ports to prevent a vMotion task from impacting VM or storage performance.
My question is, when I perform a clone operation from one storage device to another storage device, is there any option to throttle that task? I've seen many articles that talk about the provisioning IP stack, but this seems to be more related to cloning between different hosts and possibly between different sites. The advantages being that you can use a different gateway and such.
However, the clone task I am interested in throttling is simply between two directly connected storage devices over ISCSI. The single ESXi host is just talking to two datastores on two different SANs that it has direct access to over ISCSI MPIO. My concern is that if I have two crazy fast SSD based arrays, what is to prevent a clone operation from consuming all of the dual 10Gb link capacity? I would want to prevent this task from adversely impacting standard VM operations or general storage performance.