Friday, May 01, 2009

A better analysis of Cassandra than most

Vladimir Sedach wrote a three-part dive into Cassandra. (Almost two months ago now. Guess I need to set up Google Alerts. Trouble is there's a surprising amount of noise around the word `cassandra.`) A few notes:
  • We now have an order-preserving partitioner as well as the hash-based one
  • Yes, if you tell Cassandra to wait for all replicas to be ack'd before calling a write a success, then you would have traditional consistency (as opposed to "eventual") but you'd also have no tolerance for hardware failures which is a main point of this kind of system.
  • Zookeeper is not currently used by Cassandra, although we have plans to use it in the future.
  • Load balancing is not implemented yet.
  • The move to Apache is finished and development is active there now.


Unknown said...

Why is getting rid of JMX a high priority? How do you get visibility into your application if it is not instrumented?

Jonathan Ellis said...

Sorry, acronym dyslexia -- we're getting rid of the vestiges of JAXP, not JMX. Thanks for the catch. :)