It's been a number of years since I worked on it. I can try to answer your questions. The calls were nearly entirely INCR calls against keys that were typically around 150 bytes long and app logic was based on the return values. I believe each node took up around 20GB of memory when saturated. Redis uses a single CPU, so core count shouldn't matter, no? I'm not entirely sure what our NIC situation was, but it was tuned to handle gigabit traffic.