Cassandra node hardware: 2 vs 4 of double specs?

Question

according to what Ive read about cassandra, it has linear performance with nodes. Ive read that cassandra recommends a minimal of 8gb of ram, and a target of 32gb ram for production, but dont know if this specs are per node, or total.

The question is;

Case A) 8x nodes of 8gb ram 4 cores - total 64gb ram and 32 cores

Case B) 4x nodes of 16gb ram 6 cores - total 64gb ram and 24 cores

Both cases costs the same, but case A has 8 additional cores, but less ram per core... Anyone has benchmarked this scenario, or knows which solution performs better?

Thanks!

Answer 1

The hardware for either case appears to be low on RAM. Generally, RAM specifications are per node - not per data center or per cluster.

A more general answer:

The performance of your specific application will impact the number of nodes required; and the hardware requirements based on bottlenecking (memory, CPU, I/O), so its nearly impossible to answer your question.

However, I would note there is an advantage to having 8 nodes vs 4 nodes when it comes to availability - something you did not mention. In general, more smaller nodes is a good way to go with Cassandra due to partitioning and availability.