As Lejoe notes, max-reserved-bandwith allows you to determine how much bandwidth CBWFQ can explictly define. However, I'm unsure how this rules interacts with a hiearchal policy, such as your example.
The parent policy doesn't define bandwidth in class-default, although its shaper defines 2.7 Mbps which is 90% of the link's 3 Mbps. Only the child policy BH class defines 2,652 Kbps, which is 98.2% of the parent shaper's 2.7 Mbps (or 88.4% of the link's 3 Mbps).
So, it appears that "max-reserved-bandwith 85" might be unnecessary for such a configuration since some of the explicit bandwidths appears to exceed it.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...