Does Ignite ExecutorService executes the callable tasks on all cluster groups or it executes only on one node based on round-robin fashion?
If i want to execute tasks on all the cluster-group nodes, which API should be used?
The executor service is a nice upgrade if you already use one locally. If you want more control -- which is sounds like you do -- you really need to be using Ignite's native compute APIs.
// Send to one node
ignite.compute().run(() -> System.out.println("Hello"));
// Send to all nodes
ignite.compute().broadcast(() -> System.out.println("Hello"));
Incidentally, "round-robbin" is the default load-balancing algorithm, but you can change that.