This document summarizes work done by an Intel software team in China to improve Apache Spark performance for real-world applications. It describes benchmarking tools like HiBench and profiling tools like HiMeter that were developed. It also discusses several case studies where the team worked with customers to optimize joins, manage memory usage, and reduce network bandwidth. The overall goal was to help solve common issues around ease of use, reliability, and scalability for Spark in production environments.