This is our third post in our series on performance tuning with Apache Cassandra. In our first post, we discussed how we can use Flame Graphs to visually diagnose performance problems. In our second post, we discussed JVM tuning, and how the different JVM settings can have an affect on different workloads. In this post, we’ll dig into a table level setting which is usually overlooked: compression. Compression options can be specified when creating or altering a table, and it defaults to enabled if not specified.