in general, you can use the SolverManager  to solve data sets in parallel utilizing multiple cores of the CPU.
However, if too many data sets are sent, they might not fit into memory, resulting in a JVM crash with OOME. In other words, yes, some kind of queuing is required. There is a quickstart showing integration with ActiveMQ Artemis , but it solves only a single dataset at any moment, so you would have to change it to use the SolverManager.
There is another quickstart showing parallel solving on OpenShift , which also integrates with ActiveMQ Artemis; just be aware that the optaplanner-operator the quickstart relies upon is still rather experimental.