in VMM 2016, disks can be configured with a Maximum IOPs option:
However, I don't know how this IOPs figure is calculated or enforced on the VM. My own tests show that it doesn't appear to match the IOPs reported by my SAN. What I can't tell is whether this is an artifact of the underlying storage layers or something else. The storage for the VM is a VHDX located on a Cluster Shared Volume on an iSCSI-connected LUN. The VM is definitely being rate-limited, but the SAN reports nothing like the IOPs figure configured for the VM.
I want to understand how this works, so that I can appropriately configure IOPs limits to avoid swamping the SAN storage backend and better share the available throughput between the competing VMs.
So, what's the relationship between:
the Maximum IOPs figure in VMM,
the IOPs reported by the guest, and
the IOPs reported by the underlying storage