[rules-users] Planner 5.3.0 Final - Issue with Local Search / Move

[duggal]

I am solving a resource allocation problem using the Planner and have run
into a few issues with the use of Local Search.
The objective is to assign tasks to a set of resources. Each task has a
start and end time and NO task should overlap each other for the same
resource. There are other rules for preference and mandate of certain tasks
to certain resources.

I am using the FIRST_FIT construction heuristic which works fine.
I have implemented a Resource Change Move which assigns a new planning
variable to my planning entity. There seem to be issues with this phase.

**Problem** -
1. While looking at the solution created at the end of the local search
phase AND comparing to the moves output in the log file. I see that there
are several instances where the log file shows a move BUT the output
solution has the entity still on the previous planning variable.
This is happening only towards the end of the phase (about last 8 steps) of
the time terminated phase.

2. I have a rule in the DRL score file which prevents overlap of allocations
of the task for the same resource. I have instances where the construction
heuristic violated this constraint. The local search solver then moved one
of the overlapping entity to another resource. However the final output
shows the constraint still EXISTS between the two entities (even though the
overlap is no longer present). As a result even though the constraints are
actually removed, the score is NOT going down as the planner constraints
still exist.
The rule used by me is as follows (Allocation is the planning entity and
resource is the variable) -
rule "noOverlapAllocations"
    when
        $allocation1 : Allocation($id : id, $resource : resource, $task :
task, resource != null)
        $allocation2 : Allocation(id > $id, resource == $resource,
isOverlap($task), $id2 : id)
    then
        insertLogical(new IntConstraintOccurrence("overlapAllocation",
ConstraintType.NEGATIVE_HARD, 1, $allocation1, $allocation2));
end

Please help me resolve these issues.

Thanks

Vikram

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