A common question we hear from potential customers is “how does Cassandra compare to DynamoDB”? We’re big fans of AWS, in fact most of our business runs on EC2, and certainly believe DynamoDB is a great solution for some use cases. Of course, we also believe that Cassandra is an outstanding solution in a lot of cases.
Generally, the datastore you choose is based on the problem you are trying to solve. Both Cassandra and DynamoDB offers incredible scale and availability. Both can serve 10’s of millions of reads and writes, both can offer a level resilience in the face of failure and both share a similar underlying architecture (dynamo) but that is where the similarities end.
The key stats are:
- 12 x m4.xl-balanced (800GB) nodes
- Replication Factor 3
- > 40,000 writes/sec (24 x7 consistent load)
- ~ 500 reads/sec consistent load (peaks at 1-2k reads/sec) at consistency level 1
- Small data per read/write
This is our current running load – the cluster is pretty well utilised but we believe we can still push it a bit harder and in particular we plan to increase the levels of read operations.