I am working on a project for which the database is the major bottleneck. For a myriad of reasons, further optimization of the on a programming level is something we want to avoid as much as possible. We would like a solution to potentially increase the speed of our site. We are currently using MySQL, and I have read that MySQL Cluster stores the entire database in memory.
Right now, we have one database server. I am considering running two equally powerful servers with MySQL cluster with enough total memory to store the entire database in memory. With that being said, have you guys noticed a considerable speed increase going from MySQL to MySQL cluster? More specifically, does the in-memory storage of the database actually speed up the database substantially? Also, what is the role of indexes if the tables are already stored in memory? Our queries involve a lot of subqueries and joins if that makes a difference. I understand that running a benchmark is the only way to truly know, but I want to gain some background information before delving into this project.