Package de.uka.ipd.sdq.dsexplore.opt4j.optimizer.heuristic.operators.impl

Class ServerConsolidationImpl

  • All Implemented Interfaces:
    ITactic
    public class ServerConsolidationImpl
extends AbstractTactic
    Implements a server consolidation heuristic. This heuristic finds two hardly utilised resource containers and reallocates all components of these two resource containers to one resource container

    • Field Detail

      • logger

        protected static org.apache.log4j.Logger logger

    • Constructor Detail

      • ServerConsolidationImpl

        public ServerConsolidationImpl​(org.opt4j.operator.copy.Copy<org.opt4j.core.Genotype> copy,
                               DSEIndividualFactory individualFactory,
                               DSEWorkflowConfiguration configuration)
        Parameters:
        copy - Used to copy genotype
        individualFactory - Used to build individual

    • Method Detail

      • doesMatchPrecondition

        public boolean doesMatchPrecondition​(DSEIndividual individual)
        Checks the precondition by trying to generate candidates and see whether the list is larger than 0.
        Parameters:
        individual -
        Returns:

      • getHeuristicCandidates

        public List<TacticsResultCandidate> getHeuristicCandidates​(DSEIndividual individual,
                                                           UtilisationResultCacheAndHelper resultsHelper)
        Generates collection of candidates by applying the server consolidation heuristic Checks whether there is one resource container r with a utilisation_r <= THRESHOLD_LOW_UTILISATION and whether there are another n used resource containers x_1 to x_n with enough free capacity (keeping the utilisation under 0.9) so that the the load of r could be distributed: Sum_{i=1}^{n} utilisation_x_i + utilisation_r < 0.9*n The number of free resource container n must not exceed the number of components deployed to r. TODO: take resource demand of deployed components into account. TODO: take utilisation of other resources into account. TODO: The counting of deployed components does not take into account that some allocation degrees are inactive if subsystems are exchanged. Thus, only genomes where all allocation options are active are supported.
        Parameters:
        individual - Individual which the heuristic should be applied to
        resultsHelper -
        Returns:
        Collection of improved individuals