Burst transfer from memory to Nios II

Your first generalization is mostly correct, if your slave doesn't need bursting then you shouldn't enable it on the master (assuming it's optional) because it doesn't buy you anything. The only time bursting might be handy in cases like these is if you want to implement a higher quality of service for one master over other masters since bursts lock the arbiter. That said you can do the same sort of thing with arbitration share. It really depends on your system and what your throughput needs are whether bursting is worth enabling or not. Enabling bursting for non-bursting slaves doesn't increase performance but if you are working with slaves that do need bursts (like PCIe for example) to be efficient then it's a good idea to make sure whatever accesses it uses bursting too.

In fact if you connect a bursting master to a non-bursting slave in SOPC Builder your efficiency decreases since for every burst through a burst adapter there is a single cycle of overhead. So if you used a burst length of 2 on the master and a non-bursting slave, you will require 3 cycles for every burst which means your efficiency is only 67% of what it would have been with bursting disabled. Qsys doesn't have this penalty since the burst adapters are improved over the SOPC Builder version.