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

[Geoffrey De Smet]

Op 16-04-12 06:36, duggal schreef:
> 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.
Tip: FIRST_FIT is good, FIRST_FIT_DECREASING is usually better.
> 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.
If you upgrade to 5.4.0.CR1, you can use the generic change move and 
generic swap move
   
http://docs.jboss.org/drools/release/5.4.0.CR1/drools-planner-docs/html_single/index.html#d0e4563
> **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.
This sounds like a genuine bug.
Could you copy paste some logging output to show the issue more clearly?

Can you check if 5.4.0.CR1 still has the issue and create a jira:
   https://issues.jboss.org/browse/JBRULES
> 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.
Smells like a memory corruption in drools-core. There is one fixed for 
5.4.0.CR1, so

First turn on <environmentMode>TRACE</...> and see what it outputs.
   
http://docs.jboss.org/drools/release/5.4.0.CR1/drools-planner-docs/html_single/index.html#d0e2873
Then upgrade to knowledge-api, drools-core and drools-compiler 5.4.0.CR1.
It's best to upgrade planner too, but you 'll need to follow this:
   
https://github.com/droolsjbpm/drools-planner/blob/master/drools-planner-distribution/src/main/assembly/filtered-resources/UpgradeFromPreviousVersionRecipe.txt
> Thanks
>
> Vikram
>
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-- 
With kind regards,
Geoffrey De Smet