I run on a high ram 7 yo machine with 32 dual cores and an SSD. I just dropped 3/4 of my RAM cards, which puts me at 64GB. This moved my sync from 100% network to about 70%. I then restarted with bn network thread configuration bumped from 16 to 20. That restores 100% network utilization without even a noticeable increase to CPU. In other words, super fast sync with the memory-mapped store does not require super hi RAM, it can compensate with cores.