/**
* This function
* @param * nbElemPerNode : Array of number of elements, per octree node
* @param * firstElemAdress : Array of Indexes.
* Gives the index(address) first element's data in the Id's array fmmData%elem, per octree node.
* @param * nbSonsPerNode : Array of number of sons, per octree node
* @param * firstSonId : Array of number of first son Id, per octree node
* @param * nodeOwners : Array of responsible mpi ranks, per octree node. (From 1 to nbRanks, Fortran's style)
* The Result of the load balancing is read here.
* @param * nodeCenters : Array of octree node centers
* @param * endlev : Array of last octree node id, per octree level
* @param * nbLevels : Number of Octree levels
* @param * maxEdge : Edge of the first octree node. (the biggest)
* @param *LBstrategy : integer used to choose the load balancing strategy
*/
void fmm_load_balance_( i64 * nbElemPerNode, i64 * firstElemAdress, i64 * nbSonsPerNode, i64 * firstSonId, i64 * nodeOwners, double * nodeCenters, i64 * endlev,
i64 * nbLevels, double * maxEdge, int * LBstrategy)
{
// MPI parameters
int size; MPI_Comm_size(MPI_COMM_WORLD, &size);
int rank; MPI_Comm_rank(MPI_COMM_WORLD, &rank);
// create Particles
vec3D center(nodeCenters[0], nodeCenters[1], nodeCenters[2]);
scale(center);
Particles p;
p.setAttributes(0,nbElemPerNode[0],*maxEdge, center);
int nbElements = nbElemPerNode[0];
p.setNewCoordinates(elements, nbElements);
p.scale();
// creatre Octree
Node<Particles> * octree = nullptr;
octree = new Node<Particles>(p);
octree -> read_octree(nbElemPerNode, firstElemAdress, nbSonsPerNode, firstSonId, nodeCenters);
// Octree useful characteristics
int height = (*nbLevels) - 1;
int nbLeaves = endlev[height] - endlev[height-1];
int firstLeave = endlev[height-1]; // endlev[height-1] +1(next node) -1(F to C)
int firstElem = 0;
int lastElem = nbElemPerNode[0]-1;
int nbNodes = endlev[height]*3;
double * centers = new double[nbNodes];
// Load Balancing useful parameters
decompo nb1ers(size);
// Load Balance
LB_Base * LBB = nullptr;
switch (*LBstrategy)
{
case MORTON_MPI_SYNC :
cout << "*** ----- MORTON -----" << endl;
LBB = new LoadBalancer<Particles, MortonSyncMPI>(octree, nb1ers, 0, 0, firstElem, lastElem, *maxEdge, center, nullptr, nullptr/*centers*/, nodeOwners, 0);
break;
case HIST_APPROX :
cout << "*** ----- KD TREE -----" << endl;
// Get a copy of the octree centers, scale them and apply load balancing strategy
copyAndScaleArray(nodeCenters, centers, nbNodes);
LBB = new LoadBalancer<Particles, HistApprox>(octree, nb1ers, 0, 0, firstElem, lastElem, *maxEdge, center, nullptr, ¢ers[firstLeave*3], &nodeOwners[firstLeave], nbLeaves);
break;
case HIST_APPROX_X :
cout << "*** ----- SAUCISONNAGE EN X -----" << endl;
// Get a copy of the octree centers, scale them and apply load balancing strategy
copyAndScaleArray(nodeCenters, centers, nbNodes);
// test rapide - saucissonnage en X
cout << "Decomposition has been modified to : " << endl;
nb1ers._list.resize(1);
nb1ers._list[0] = size;
nb1ers.display();
LBB = new LoadBalancer<Particles, HistApprox>(octree, nb1ers, 0, 0, firstElem, lastElem, *maxEdge, center, nullptr, ¢ers[firstLeave*3], &nodeOwners[firstLeave], nbLeaves);
break;
default :
cerr << "No identified Load Balancing strategy" << endl;
exit(0);
}
LBB->run();
delete Particles::_coordinates;
cout << "---- Load Balancing ----> TERMINATED !" <<endl;
int * counters = new int[size + 1]();
}
void FMM_load_balance(string file, int nbParticles, double dist, double tolerance, double maxEdge, int LBStrategy)
{
int size;
MPI_Comm_size(MPI_COMM_WORLD,&size);
decompo nb1ers(size);
int first = 0;
int last = nbParticles-1;
vec3D center(0,0,0);
Node<Particles> * treeHead = nullptr;
Gaspi_communicator * gComm = nullptr;
// tree creation
Particles p;
if ( LBStrategy == HIST_EXACT ||
LBStrategy == HIST_APPROX ||
LBStrategy == MORTON_MPI_SYNC)
{
p.loadCoordinatesASCII(nbParticles, file);
}
else
{
gComm = new Gaspi_communicator(512, nbParticles);
p.loadCoordinatesASCII(nbParticles, file, gComm);
}
p.scale();
treeHead = new Node<Particles>(p);
// Node Owners array
i64 * nodeOwners = nullptr;
// Load Balancing
LB_Base * LBB = nullptr;
switch (LBStrategy)
{
case HIST_EXACT :
cout <<"--> Exact Histograms" << endl;
LBB = new LoadBalancer<Particles, HistExact> (treeHead, nb1ers, dist, tolerance, first, last, maxEdge, center, gComm, nullptr, nodeOwners, 0);
LBB->run();
break;
case HIST_APPROX :
cout <<"--> Approx Histograms" << endl;
LBB = new LoadBalancer<Particles, HistApprox> (treeHead, nb1ers, dist, tolerance, first, last, maxEdge, center, gComm, nullptr, nodeOwners, 0);
LBB->run();
break;
case MORTON_MPI_SYNC :
cout <<"--> Morton DFS, with tolerance : " << tolerance << endl;
LBB = new LoadBalancer<Particles, MortonSyncMPI>(treeHead, nb1ers, dist, tolerance, first, last, maxEdge, center, gComm, nullptr, nodeOwners, 0);
LBB->run();
break;
case MORTON_GASPI_ASYNC :
cout <<"--> Morton DFS Async, with tolerance : " << tolerance << endl;
LBB = new LoadBalancer<Particles, MortonAsyncGASPI>(treeHead, nb1ers, dist, tolerance, first, last, maxEdge, center, gComm, nullptr, nodeOwners, 0);
LBB->run();
break;
default :
cerr << "No load balancing strategy detected !";
exit(5);
}
}