Hey, Mutations taking longer than rpc_timeout will be dropped because coordinator won't be waiting for the coordinator and will return TimeoutException to the client, if it doesn't reach the consistency level [1].
In case of counters though, since counter mutations aren't idempotent, the client is not supposed to retry an increment on TimeoutException. So why doesn't a counter mutation gets processed regardless of rpc_timeout? Cheers, Omid [1] http://wiki.apache.org/cassandra/FAQ#dropped_messages
