My question relates specifically to ZFS/COMSTAR but I assume is generally applicable to any iSCSI system:

Should one prefer to create a target for every LUN that you want to expose? Or is it good practise to have a single target with multiple LUNs?

Does either approach have a performance impact? And is there some crossover point where the other approach makes sense?

The use case is for VM disks, where each disk (zvol) is a LUN. So far we have created a a separate target for each VM; but a single target that contains all the LUNs would probably greatly simplify management... but we may need hundreds of LUNs per a single target. (And then possibly tens of initiator connections to that target)