Percona Live was held at the beginning of April this year and the Acquia team was there. This was a really great conference and I want to start by encouraging any DBA/database developer who uses MySQL in a production environment to go to the Percona Live conference. It's a great place to hear about new functionality, new products and how other companies are using MySQL at scale. Large companies like Google, Facebook and Twitter as well as hot startups like Box all send representatives to share their knowledge.
At Acquia we use the Percona version of MySQL as our standard data store for all hosted Drupal sites as well as for lots of internal projects. Since all our production servers use MySQL replication to provide high availability and our databases are continuously growing we're always looking to get better performance out of replication. The new replication enhancements in MySQL 5.6 and 5.7 are promising better performance but need some work in the application and tools to deliver on that performance. At this year's conference I decided to take a new look at the current state of external high availability and failover solutions to see what enhancements they could deliver and how much effort would be involved in implementing them.
I want to summarize and compare four of the more interesting products that are currently available. I will also point out if there are Drupal specific things to keep in mind when choosing between them. All these tools are open source and free.