The 1 GigE era is coming to an end and is rapidly being replaced by 10 GigE. This means less physical network connections and that network traffic with different patterns and needs will merge together on the same network.
This may directly impact performance and predictability due to lack of isolation, scheduling, and arbitration. Network I/O control can be used to prioritize different network traffic on the same pipe.
You cannot have guaranteed bandwidth as long as you don't limit other traffic, so there'll always be enough available bandwidth.
As some traffic (that is, vMotion) might not be used all the time, we'll have temporarily unused bandwidth with static limits. As long as there is no congestion, this doesn't really matter, but if there is, then you're limiting the bandwidth for traffic even when there is bandwidth available, which is not a good way to deal with congestion.
For some VMkernel traffic, VMware recommends dedicated...