Again: Local Search phase (1) needs to start from an initialized solution

[Adalbert Schwafel]

Hi, using 8.8.0.Final, I get again the below error after completion of the construction heuristics phase. 

18:13:10 INFO  Solving started: time spent (1133), best score (-400init/0hard/0soft), environment mode (REPRODUCIBLE), move thread count (1), random (JDK with seed 0).

18:16:10 INFO  Construction Heuristic phase (0) ended: time spent (181140), best score (-246init/0hard/0soft), score calculation speed (3126/sec), step total (154).

Exception in thread "main" java.lang.IllegalStateException: Local Search phase (1) needs to start from an initialized solution, but the planning variable (OB.start) is uninitialized for the entity

My solver config contains

<constructionHeuristic>
    <constructionHeuristicType>FIRST_FIT</constructionHeuristicType>
</constructionHeuristic>
<localSearch>
    <localSearchType>TABU_SEARCH</localSearchType>
</localSearch>

What am I doing wrong?

[Kent Zhang]

In default, a solver includes 2 phases - Construction Heuristic, and Local Search. When the Construction Heuristic terminated without completion and Local Search started, this exception appeared.
Try to increase the unimprovedXXXXSpentLimit in the termination setting, to ensure the CH phase is complete before timeout.

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With kind regards,

Kent Zhang

[Adalbert Schwafel]

Thanks a lot Kent, this solves the issue. However, I don't understand how the termination criterion applies to the two phases (CH and Local Search). Do they apply separately to both? Why does Optaplanner proceed to Local Search if CH didn't terminate?

[Kent Zhang]

Because in the CH phase, the score will not be improved. If the CH phase reaches the stop condition (such as unimprovedXXXXSpentLimit  ), it will be regarded as the end of this phase and start the next phase.

You can set the stop condition for each phase:

        SolverConfig solverConfig = SolverConfig.createFromXmlFile(configFile);

        TerminationConfig ch_terminationConfig = new TerminationConfig();
        ch_terminationConfig.setUnimprovedSecondsSpentLimit(60L);
        ch_terminationConfig.setSecondsSpentLimit(300L);
        solverConfig.getPhaseConfigList().get(0).setTerminationConfig(ch_terminationConfig);

        TerminationConfig ls_terminationConfig = new TerminationConfig();
        ls_terminationConfig.setUnimprovedSecondsSpentLimit(30L);
        ls_terminationConfig.setSecondsSpentLimit(300L);
        solverConfig.getPhaseConfigList().get(1).setTerminationConfig(ls_terminationConfig);

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