I am developing a solver using Optaplanner 6.1.0, similar to the Vehicle Routing Problem. When I run my solver on 700 installers and 200 bookings, it will successfully solve the planning problem. But, when I used against a larger dataset (700 installers and 1220 bookings), I get
Caused by: java.lang.IllegalStateException: Local Search phase started with an uninitialized Solution. First initialize the Solution. For example, run a Construction Heuristic phase first.
but right before the exception,
16:10:40,378 INFO [DefaultConstructionHeuristicPhase] [http-listener-1(4)] Construction Heuristic phase (0) ended: step total (194), time spent (30693), best score (-1hard/-688803soft).
I am using <constructionHeuristicType>FIRST_FIT_DECREASING</constructionHeuristicType>
in my config.
Am I using it wrong?
Maybe the value range for a planning variable is empty. Especially with value range provider from entity, this is more likely. Feel free to file a jira that the error message should improve in such a case.
Diagnostic todo: Comment out the local solver phase, run the solver (so it only does the construction heuristic) and then iterate through the planning entities and print out the value for each planning value. Check if there are any nulls in there.
The fact that you have 194 steps, instead 200 steps in your CH indicates this. (If those other 6 planning entities are immovable, this won't trigger this exception (more info), so that's not the problem.)