Speculative execution

Speculative query execution is an optimization technique where a driver pre-emptively starts a second execution of a query against another node, before the first node has replied.

There are multiple speculative execution strategies that the driver can use. Speculative execution can be configured for the whole whole Session during its creation.

Available speculative execution strategies:

• Simple
• Latency Percentile

Speculative execution is not enabled by default, and currently only non-iter session methods use it.