Building always on software with Apache Cassandra

So what do we mean by always on? Five 9s, ten 9s? This talk is about the hardest part of the stack to make available: the database.;Do you remember CAP theorem from University? How many AP systems have you built or used? Trading off consistency for being always on is a decision some companies have had to make (we can’t live without Netflix or Amazon can we?). ;Most of the talk will be about Apache Cassandra. However we'll first go through the general requirements of any database system when you want to remain online 24/7, this will help you to evaluate any database technology. ;What you’ll learn is if you want to build an AP systems with a database like Cassandra, we as developers need to get out of a relational mindset (no free lunch). We need to model our data differently and develop with fault tolerance in mind to handle things like: concurrent updates from multiple datacenters, hardware and network failure and throughputs in the millions of transactions a second.