I've worked in a similar situation -- a transaction processing system with ~1M tx/day and ~2TB total data. They used 15 Cassandra nodes and a monster Redshift c

I've worked in a similar situation -- a transaction processing system with ~1M tx/day and ~2TB total data. They used 15 Cassandra nodes and a monster Redshift cluster (>64 CPU cores, ~512GB RAM, 30+TB disk) for the OLTP and OLAP queries. I almost can't put Cassandra and Redshift on my resume because when more knowledgeable people ask about my experience with them, that pathetic use case makes me look bad by association.