I am inexperienced with Cassandra, but I have some experience with SQL-based relational databases.
I have been unable to find best practices information about how to maintain Cassandra once deployed. Is it necessary to VACUUM the database? I should think that read/write loads cause fragmentation in the storage.
Or more generally: what are the best practices for maintaining a Cassandra production deployment? What has to be done at regular intervals to maintain the health of the system? The Operations manual really doesn't discuss this aspect.