The Synchronous Data Center
Yang Tian, Robert Gifford, Andreas Haeberlen, Linh Thi Xuan Phan · 2019
Today, distributed systems are typically designed to be largely asynchronous. Designers assume that the network can drop or significantly delay messages at unpredictable times, that there is no way to know how quickly a node might process a message, or how soon it might respond, and that the clocks of different nodes are at most loosely synchronized. These assumptions are certainly safe, but they come at a price: many applications really do need predictable performance, which, on top of an asynchronous system, has to be approximated at great cost and with lots of redundancy, and many distributed protocols for asynchronous systems are much more complex and expensive than their synchronous counterparts.