loadbalancing.cpp

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#include "loadbalancing.h"
 
#include "tarch/logging/Log.h"
 
#include "peano4/parallel/SpacetreeSet.h"
 
#include "peano4/grid/GridStatistics.h"
 
#include "tarch/tarch.h"
 
#include <stdlib.h>
 
 
namespace {
  // If I don't instantiate it here, i.e. outside of a function, then I run risk
  // that it is initialised late and thus has the wrong time stamp.
  tarch::logging::Log _log( "toolbox::loadbalancing" );
}
 
 
void toolbox::loadbalancing::dumpStatistics() {
  std::ostringstream msg;
 
  int sumLocal  = 0;
  int sumRemote = 0;
  std::set<int> idsOfLocalSpacetrees = peano4::parallel::SpacetreeSet::getInstance().getLocalSpacetrees();
 
  msg << idsOfLocalSpacetrees.size() << " tree(s): ";
 
  for (auto p: idsOfLocalSpacetrees) {
    msg << "(#" << p << ":"
        << peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(p).getNumberOfLocalUnrefinedCells()
        << "/"
        << peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(p).getNumberOfRemoteUnrefinedCells()
        << ")";
    sumLocal  += peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(p).getNumberOfLocalUnrefinedCells();
    sumRemote += peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(p).getNumberOfRemoteUnrefinedCells();
  }
  if (idsOfLocalSpacetrees.empty()) {
    msg << "no trees hosted on this node - therefore no load";
  }
  else {
    msg << " total=" << sumLocal << "/" << sumRemote << " (local/virtual)";
  }
 
  logInfo( "dumpStatistics()", msg.str() );
}
 
 
int toolbox::loadbalancing::getWeightOfHeaviestLocalSpacetree() {
  std::set<int> idsOfLocalSpacetrees = peano4::parallel::SpacetreeSet::getInstance().getLocalSpacetrees();
  int heaviestSpacetree      = -1;
  int maxLocalUnrefinedCells = -1;
 
  for (auto p: idsOfLocalSpacetrees) {
    if (
      peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(p).getNumberOfLocalUnrefinedCells()>maxLocalUnrefinedCells
      and
      peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(p).getNumberOfLocalUnrefinedCells()>=ThreePowerD
    ) {
      maxLocalUnrefinedCells = peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(p).getNumberOfLocalUnrefinedCells();
      heaviestSpacetree = p;
    }
  }
 
  logDebug( "getWeightOfHeaviestLocalSpacetree()", "id=" << heaviestSpacetree << ", #octants=" << peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(heaviestSpacetree).getNumberOfLocalUnrefinedCells() );
  return heaviestSpacetree==-1 ? -1 : peano4::parallel::SpacetreeSet::getInstance().getGridStatistics(heaviestSpacetree).getNumberOfLocalUnrefinedCells();
}