Alibaba’s 11.11 Global Shopping Festival, hosted annually on November 11, is the world’s largest 24-hour online shopping event. On this day, we process trillions of events in realtime to give the best experience to users of our e-commerce platform. In this talk, we will dive into the scale and performance challenges we faced creating a real time infrastructure. These challenges include bottlenecks in the network layer, scheduling, and distributed file system. We will also talk about the tools that we used to identify and analyze these problems.