Improved Client Request Routing for Apache Cassandra®

The new default load balancing algorithm in DataStax Drivers aims to reduce long tail latency and improve overall response times by using a modified version of the Power of Two Random Choices algorithm. This algorithm selects two replicas at random and picks the one with fewer in-flight requests as coordinator, while also considering whether a node has not sent back any response in the last few hundred milliseconds. The new approach outperforms previous methods and is being rolled out across all client drivers.