Cassandra is written in Java and while there are a lot of tricks to optimize it there are limits.
While C++ does have an advantage of raw performance it's ScyllaDB's seastar implementation that helps a lot. Think of every core in the machine as a node so there is no context switching and better use of the cpu cache. More than that the ScyllaDB team are extremely performance focused something that I can't say for Cassandra
It's the architectural choices more than the language (one thread per core, async, event loops). But I'm sure the c++ does have some benefit over Java.
> while achieving significantly higher throughputs and lower latencies [compared to Cassandra]
Do they really get all that just because it's in C++? Anyone familiar with both of them?