This document summarizes Baidu's use of Apache Spark and Tachyon for interactive data analytics. It describes Baidu's need for faster interactive queries to analyze petabytes of data within 30 seconds. Baidu implemented a query architecture using Spark, SQL and UDFs over Tachyon for hot data and HDFS storage. This provided over 50x acceleration compared to MapReduce, enabling 95% of queries to finish within 30 seconds. While Spark has improved performance, MapReduce still handles high throughput batch workloads at larger scale. Future opportunities include hardware acceleration and continued Spark optimizations for memory management and query planning.