Resumen
As more data moves into the cloud, many developers find themselves grappling with the prospect of system failure at ever-widening scales. In this deeply intertwined environment, software designers have to plan for a bewildering array of potential failure points. Building large-scale fault-tolerant systems inevitably involves trade-offs in terms of cost, performance, and development time. At Microsoft, researcher Rama Kotla has proposed a new Byzantine fault tolerance replication protocol known as Zyzzyva, that strives to improve performance by using a technique called speculation to achieve low performance overheads. Also at Microsoft, director Chandu Thekkath has been pioneering an alternative approach to fault tolerance for Microsoft's Live Services, creating a single "configuration master" to coordinate recovery from machine failures across multiple data services. Many developers still wrestle with the cost and performance trade-offs of fault tolerance, however, and a number of large sites still seem willing to accept a certain degree of system failure as a cost of doing business on the Web.