The document discusses using Spark and Tachyon to build an interactive data service at Baidu. It summarizes Tachyon basics and new features. It then discusses how Spark and Tachyon were used to build a service that provides interactive queries over petabytes of data stored in Baidu's data warehouse, achieving 30x speed improvements over MapReduce. The service uses Spark for computation, Tachyon for caching data in memory, and a cache management system to improve query performance. Future work areas discussed include improving the caching system and supporting more user scenarios.