Apache Kafka is a highly popular distributed system used by many organizations to connect systems, build microservices, create data mesh, etc. However, as a distributed system, understanding its performance could be a challenge, so many moving parts exist. In this talk, I review the key moving parts (producers, consumers, replication, network, etc), a strategy to measure and interpret the performance results for consumers and producers and a general guideline for deciding about performance in Apache Kafka. You will learn a proven method to measure, evaluate and optimize the performance of an Apache Kafka based infrastructure. A key skill for low throughput users, but especially for the biggest scale deployments.