I am evaluating MySQL Cluster as a possible replacement for an InnoDB schema. So far, I have tested it with 10s of MB of data, and found MySQL Cluster slower than InnoDB; however, I have been told MySQL Cluster scales much better.
How much data does it take to show a performance benefit to MySQL Cluster vs. an InnoDB schema? Or, is there a better way to demonstrate MySQL Cluster's merits?
EDIT
Perhaps an important note: My cluster is currently a heterogeneous cluster with 4 machines. On each machine, I have given an equal amount of Data and Index Memory; 4GB, 2GB, 2GB, and 1GB respectively. The machines are running i7's and are connected over a Gigabit Lan. NumOfReplicas is set to 2.
EDIT
This application is a low-usage analytics database, which has roughly 3 tables >= 200M rows and 5 tables <= 10K rows. When we use it, it takes 15 seconds to run our aggregate functions. My boss asked me to research MySQL Cluster, to see if we could increase performance, since we thought aggregate functions could run pretty well in parallel.