Next generation compute models need to handle extreme amounts of data which means getting data closer to the compute engine in much shorter time-frames.

In relative terms, cpu-cache,cpu-memory, cpu-flash storage can be measured in secs/mins/days whereas network write / replication updates (as in N-Tier models with lots of small systems) can be measured in months.

Even if cheaper and more available, how does one reconcile using rack models with the above when the over-riding goal is to reduce overall solution latency?

We are at the beginning of network tier consolidation whereby next generation models will be based on fewer, but much larger blade type servers (TB’s non-volatile local memory) that utilize high speed interconnects (e.g. CAPI, RoCEv2, others) e.g. clusters of big systems.