Scylla is a C++ rewrite of cassandra, the threading has been better as well with thread-per-core. Cassandra 4.0 has some thread-per-core rearchitecture so it re

Scylla is a C++ rewrite of cassandra, the threading has been better as well with thread-per-core. Cassandra 4.0 has some thread-per-core rearchitecture so it remains to be seen if Scylla has performance advantages it used to tout. I have not checked if Scylla ever caught up to Cassandra 3.0's feature set, last I checked it had not. It may be "going its own way" on features as well. I believe (they can correct me). My personal recommendation would be to start with Cassandra, and when operations allow it, move to scylla if performance testing shows it is better. There is also exotic stuff like Rocksandra. Cassandra and Scylla are fundamentally similar in operations (add/remove nodes, scaling, etc). The scylla folks will contend the operations are easier since they get more perf per node so you need less nodes. It's a good idea with cassandra / scylla to bootstrap with a performance testing, data loading, provisioning loop. It gets you used to operations and the tooling for backups, loads, and load testing and metrics.