This isn't the right forum for that kind of discussion. I recommend going on Quora which already has a few good threads on the subject, answered by FB folks, namely:
http://www.quora.com/Why-did-Facebook-pick-HBase-instead-of-Cassandra-for-the-new-messaging-platform and http://www.quora.com/How-does-HBase-write-performance-differ-from-write-performance-in-Cassandra-with-consistency-level-ALL Thanks, J-D 2010/11/19 MauMau <[email protected]>: > Hello, (especially Mr. Jonathan Gray, Facebook folks), > > I'm sorry for mentioning particular people in a public ML. > > I saw the following note from Facebook that says Facebook chose HBase, not > Cassandra, as the storage for the next messaging infrastructure. > > http://www.facebook.com/notes/facebook-engineering/the-underlying-technology-of-messages/454991608919 > > I'm glad to see this news because I believe that HBase will be used more > broadly than Cassandra and recommended HBase to my boss and colleagues. > (However, I understand Cassandra has unique good features.) > > I'd like to know why Facebook, the creator of Cassandra, did not choose > Cassandra. The above note only describes the reason in one sentence: > > "We found Cassandra's eventual consistency model to be a difficult pattern > to reconcile for our new Messages infrastructure." > > What kind of operations/features of the new Message didn't Cassandra work > well for? Counting message, users or something like that because Cassandra > needs ZooKeeper to count things correctly? Otherwise, eventual consistency > leads to the undesirable situation where newer messages could appear in the > inbox without older ones appearing? I'd appreciate if you could share your > concrete experience/opinions and let us know when HBase fits better or > Cassandra is difficult to adopt. > > Anyone's opinions or guesses will be appreciated. > > Best regards, > - Maumau > >
