[touisteur]

Low-level, DMA on PCIe stuff like GPUdirect and StorageDirect is a (limited, low-level, frustrating) form of disaggregated computing, if you think of DMA engines as tiny specific cores (and FPGA people have been using the PCIe bus and crazy 'DMAs' for this kind of stuff for a long time now).

On the high end you got your GPUs and accelerators, and recently all kinds of combinations of NIC, CPUs and GPUs, and on the extreme of the spectrum some of them also have ultra high bandwidth interconnect (mostly nvlink) that make the whole concept of disaggregated computing (in one host) more than viable and exciting.

It's just a big pain right now to program, synchronize, schedule all these async units and their async transfers, all that in a somewhat portable way.