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Use partitioning neighborhood directly for hypergraph
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@lkotipal
lkotipal committed Feb 9, 2024
1 parent 582cc05 commit f0b1294
Showing 1 changed file with 10 additions and 110 deletions.
120 changes: 10 additions & 110 deletions dccrg.hpp
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Original file line number Diff line number Diff line change
Expand Up @@ -2825,110 +2825,6 @@ template <
return ret;
}

std::set<uint64_t> get_vlasov_neighbors(
const uint64_t cell,
const int neighborhood_id,
const int dimension,
const int stencil_width
) const {
std::set<uint64_t> ret;
const auto* p = get_neighbors_of(cell, neighborhood_id);
if (!p) {
std::cerr << "Cell " << cell << ", neighborhood " << neighborhood_id << ", dimension " << dimension << " not found" << std::endl;
return ret;
}

// Create list of unique distances
std::set<int> distances_plus;
std::set<int> distances_minus;
std::set<uint64_t> found_neighbors_plus;
std::set<uint64_t> found_neighbors_minus;
/** Using sets of cells as well, we should only get one distance per
(potentially less refined) cell. This should result in safe behaviour
as long as the neighborhood of a cell does not contain cells with a
refinement level more than 1 level apart from the cell itself.
*/
for (const auto& [neighbor, coords] : *p) {
if(coords[dimension] > 0) {
if (!found_neighbors_plus.count(neighbor)) {
distances_plus.insert(coords[dimension]);
found_neighbors_plus.insert(neighbor);
}
}
if(coords[dimension] < 0) {
if (!found_neighbors_minus.count(neighbor)) {
distances_minus.insert(-coords[dimension]);
found_neighbors_minus.insert(neighbor);
}
}
}

int iSrc = stencil_width - 1;
// Iterate through positive distances for VLASOV_STENCIL_WIDTH elements starting from the smallest distance.
for (const auto& distance : distances_plus) {
if (iSrc < 0)
break; // found enough elements
for (const auto& [neighbor, coords] : *p) {
if (neighbor == error_cell)
continue;
if (coords[dimension] == distance) {
if (ret.count(neighbor))
continue;
ret.insert(neighbor);
}
} // end loop over neighbors
iSrc--;
} // end loop over positive distances

iSrc = stencil_width - 1;
// Iterate through negtive distances for VLASOV_STENCIL_WIDTH elements starting from the smallest distance.
for (const auto& distance : distances_minus) {
if (iSrc < 0)
break; // found enough elements
for (const auto& [neighbor, coords] : *p) {
if (neighbor == error_cell)
continue;
if (coords[dimension] == distance) {
if (ret.count(neighbor))
continue;
ret.insert(neighbor);
}
} // end loop over neighbors
iSrc--;
} // end loop over negative distances

return ret;
}

// Get actual Vlasov stencil neighbors
// Assumes linear 3 linear stencils from neighborhood_id to neighborhood_id + 2
std::set<uint64_t> get_vlasov_neighbors(
const uint64_t cell
) const {
int stencil_width {0};
switch (neighborhood_length) {
case 1:
break;
case 3:
stencil_width = 2;
break;
case 5:
stencil_width = 3;
break;
default:
// Placeholder error
std::cerr << "Weird stencil width" << std::endl;
break;
}

std::set<uint64_t> ret;
for (int dim = 0; dim < 3; ++dim) {
auto neighs_dim = get_vlasov_neighbors(cell, partitioning_neighborhood_id + dim, dim, stencil_width);
ret.insert(neighs_dim.begin(), neighs_dim.end());
}
return ret;
}


/*!
Returns true if given cell's neighbor types match given criterion, false otherwise.
Expand Down Expand Up @@ -11394,6 +11290,7 @@ template <


/*!
Graph partitioning
Writes the number of neighbors into number_of_neighbors for all cells given in global_ids.
*/
static void fill_number_of_neighbors_for_cells(
Expand Down Expand Up @@ -11431,12 +11328,13 @@ template <
return;
}

number_of_neighbors[i] = dccrg_instance->get_vlasov_neighbors(cell).size();
number_of_neighbors[i] = dccrg_instance->get_neighbors_to(cell, dccrg_instance->partitioning_neighborhood_id)->size();
}
}


/*!
Graph partitioning
Writes neighbor lists of given cells into neighbors, etc.
*/
static void fill_neighbor_lists(
Expand Down Expand Up @@ -11480,7 +11378,9 @@ template <

number_of_neighbors[i] = 0;

for (const auto& neighbor: dccrg_instance->get_vlasov_neighbors(cell)) {
// We consider the communication weight from this cell to others
auto weight {dccrg_instance->get_communication_weight(cell)};
for (const auto& [neighbor, dir] : *dccrg_instance->get_neighbors_to(cell, dccrg_instance->partitioning_neighborhood_id)) {
// Zoltan 3.501 crashes in hierarchial if a cell is a neighbor to itself
if (neighbor == 0 || neighbor == cell) {
continue;
Expand All @@ -11494,7 +11394,7 @@ template <

// weight of edge from cell to *neighbor
if (number_of_weights_per_edge > 0) {
edge_weights[current_neighbor_number] = dccrg_instance->get_communication_weight(neighbor);
edge_weights[current_neighbor_number] = weight;
}

current_neighbor_number++;
Expand Down Expand Up @@ -11547,7 +11447,7 @@ template <


/*!
Writes the number of hyperedges (self + one per neighbor cell) in the grid for all cells on this process.
Writes the number of connections (self + one per neighbor cell) in the grid for all cells on this process.
*/
static void fill_number_of_hyperedges(
void* data,
Expand Down Expand Up @@ -11575,7 +11475,7 @@ template <

*number_of_connections = 0;
for (const auto& item: dccrg_instance->cell_data) {
(*number_of_connections) += 1 + dccrg_instance->get_vlasov_neighbors(item.first).size();
(*number_of_connections) += 1 + dccrg_instance->get_neighbors_to(item.first, dccrg_instance->partitioning_neighborhood_id)->size();
}
}

Expand Down Expand Up @@ -11634,7 +11534,7 @@ template <
// add a connection to the cell itself from its hyperedge
connections[connection_number++] = item.first;

for (const auto& neighbor: dccrg_instance->get_vlasov_neighbors(item.first)) {
for (const auto& [neighbor, dir]: *dccrg_instance->get_neighbors_to(item.first, dccrg_instance->partitioning_neighborhood_id)) {
// Zoltan 3.501 crashes in hierarchial if a cell is a neighbor to itself
if (neighbor == 0 || neighbor == item.first) {
continue;
Expand Down

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