Here are some interesting dates in the history of the RAMCloud project (reverse chronological order):

Fall 2008, Winter 2009: Various informal discussions about the RAMCloud concept between John Ousterhout, Mendel Rosenblum, Guru Parulkar, Balaji Prabhakar, David Erickson, and others. John's initial goal is to support 1μs RPCs, but he backs off to 5-10μs after Balaji explains the state of current datacenter switching fabrics.