We're using Cassandra in production for a bunch of things at Twitter. A few examples: Our geo team uses it to store and query their database of places of interest. The research team uses it to store the results of data mining done over our entire user base. Those results then feed into things like @toptweets and local trends. Our analytics, operations and infrastructure teams are working on a system that uses cassandra for large-scale real time analytics for use both internally and externally.

For now, we're not working on using Cassandra as a store for Tweets. This is a change in strategy. Instead we're going to continue to maintain our existing Mysql-based storage. We believe that this isn't the time to make large scale migration to a new technology. We will focus our Cassandra work on new projects that we wouldn't be able to ship without a large-scale data store.




We're investing in Cassandra every day. It'll be with us for a long time and our usage of it will only grow.



First, Twitter won’t be using the Cassandra database system to store tweets. Second, Cassandra will be used for Twitter’s realtime analytics product. The one they haven’t officially announced yet.


このところ、Cassandra関連では、NoSQL magazineで、

  • Facebook is still using Cassandra internally for the inbox search, but they are using their own version
  • even if except the initial code share Facebook has stopped contributing to the Cassandra project, the community on ASF is doing well (read growing)



ちなみに、Twitterが、Cassandraの本採用を断念。「いまは切り替えの時期ではない」 - Publickeyでは、「本採用を断念」とありますが、Tweetの保存以外のプロダクトでは使用を拡大していこうとしているので、以前に比べ後退しているとは言え、「TwitterはCassandraを本採用している」と私は思うのですが、どうなのでしょう。