diff --git a/src/mesh/Connectivity.hpp b/src/mesh/Connectivity.hpp
index 24d9ef656f0cdd0746db0ee2f27881ce5244c8b0..aa1a471d6e84b554c1715ca7eecc7a2361744b07 100644
--- a/src/mesh/Connectivity.hpp
+++ b/src/mesh/Connectivity.hpp
@@ -19,7 +19,6 @@
#include <utils/PugsTraits.hpp>
#include <utils/PugsUtils.hpp>
-#include <algorithm>
#include <iostream>
#include <set>
#include <vector>
diff --git a/src/utils/CMakeLists.txt b/src/utils/CMakeLists.txt
index 333d37768f20fa91f47c342a64e809f526142095..bc66a97faf800dc0a10be3165f8d4f2c94059010 100644
--- a/src/utils/CMakeLists.txt
+++ b/src/utils/CMakeLists.txt
@@ -19,6 +19,7 @@ add_library(
PartitionerOptions.cpp
PETScWrapper.cpp
PluginsLoader.cpp
+ PTScotchPartitioner.cpp
PugsUtils.cpp
RandomEngine.cpp
ReproducibleSumManager.cpp
diff --git a/src/utils/PTScotchPartitioner.cpp b/src/utils/PTScotchPartitioner.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..e86acfa4494c437dfbe8886a83d6ecbf01f514f2
--- /dev/null
+++ b/src/utils/PTScotchPartitioner.cpp
@@ -0,0 +1,110 @@
+#include <utils/PTScotchPartitioner.hpp>
+
+#include <utils/pugs_config.hpp>
+
+#ifdef PUGS_HAS_PTSCOTCH
+
+#include <utils/Exceptions.hpp>
+#include <utils/Messenger.hpp>
+
+#include <ptscotch.h>
+
+#include <iostream>
+#include <vector>
+
+Array<int>
+PTScotchPartitioner::partition(const CRSGraph& graph)
+{
+ std::cout << "Partitioning graph into " << rang::style::bold << parallel::size() << rang::style::reset
+ << " parts using " << rang::fgB::green << "PTScotch" << rang::fg::reset << '\n';
+
+ MPI_Group world_group;
+ MPI_Comm_group(parallel::Messenger::getInstance().comm(), &world_group);
+
+ MPI_Group mesh_group;
+ std::vector<int> group_ranks = [&]() {
+ Array<int> graph_node_owners = parallel::allGather(static_cast<int>(graph.numberOfNodes()));
+ std::vector<int> grp_ranks;
+ grp_ranks.reserve(graph_node_owners.size());
+ for (size_t i = 0; i < graph_node_owners.size(); ++i) {
+ if (graph_node_owners[i] > 0) {
+ grp_ranks.push_back(i);
+ }
+ }
+ return grp_ranks;
+ }();
+
+ MPI_Group_incl(world_group, group_ranks.size(), &(group_ranks[0]), &mesh_group);
+
+ MPI_Comm partitioning_comm;
+ MPI_Comm_create_group(parallel::Messenger::getInstance().comm(), mesh_group, 1, &partitioning_comm);
+
+ Array<int> partition;
+ if (graph.numberOfNodes() > 0) {
+ SCOTCH_Strat scotch_strategy;
+ SCOTCH_Dgraph scotch_grah;
+
+ SCOTCH_stratInit(&scotch_strategy); // use default strategy
+ SCOTCH_dgraphInit(&scotch_grah, partitioning_comm);
+
+ const Array<const int>& entries = graph.entries();
+ const Array<const int>& neighbors = graph.neighbors();
+
+ static_assert(std::is_same_v<int, SCOTCH_Num>);
+
+ SCOTCH_Num* entries_ptr = const_cast<int*>(&(entries[0]));
+ SCOTCH_Num* neighbors_ptr = const_cast<int*>(&(neighbors[0]));
+
+ if (SCOTCH_dgraphBuild(&scotch_grah,
+ 0, // 0 for C-like arrays
+ graph.numberOfNodes(), //
+ graph.numberOfNodes(), //
+ entries_ptr, //
+ nullptr, //
+ nullptr, //
+ nullptr, // optional local node label array
+ graph.neighbors().size(), //
+ graph.neighbors().size(), //
+ neighbors_ptr, //
+ nullptr, //
+ nullptr) != 0) {
+ // LCOV_EXCL_START
+ throw UnexpectedError("PTScotch invalid graph");
+ // LCOV_EXCL_STOP
+ }
+
+ partition = Array<int>(graph.numberOfNodes());
+
+ SCOTCH_Num* partition_ptr = static_cast<SCOTCH_Num*>(&(partition[0]));
+
+ if (SCOTCH_dgraphPart(&scotch_grah, //
+ parallel::size(), //
+ &scotch_strategy, //
+ partition_ptr) != 0) {
+ // LCOV_EXCL_START
+ throw UnexpectedError("PTScotch Error");
+ // LCOV_EXCL_STOP
+ }
+
+ SCOTCH_dgraphExit(&scotch_grah);
+ SCOTCH_stratExit(&scotch_strategy);
+ }
+
+ MPI_Comm_free(&partitioning_comm);
+ MPI_Group_free(&mesh_group);
+ MPI_Group_free(&world_group);
+
+ return partition;
+}
+
+#else // PUGS_HAS_PTSCOTCH
+
+Array<int>
+PTScotchPartitioner::partition(const CRSGraph& graph)
+{
+ Array<int> partition{graph.entries().size() - 1};
+ partition.fill(0);
+ return partition;
+}
+
+#endif // PUGS_HAS_PTSCOTCH
diff --git a/src/utils/PTScotchPartitioner.hpp b/src/utils/PTScotchPartitioner.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..cefb0a1df2e1c39966d6c8ed0eaffe655a836df0
--- /dev/null
+++ b/src/utils/PTScotchPartitioner.hpp
@@ -0,0 +1,19 @@
+#ifndef PT_SCOTCH_PARTITIONER_HPP
+#define PT_SCOTCH_PARTITIONER_HPP
+
+#include <utils/Array.hpp>
+#include <utils/CRSGraph.hpp>
+
+class PTScotchPartitioner
+{
+ private:
+ friend class Partitioner;
+
+ // Forbids direct calls
+ static Array<int> partition(const CRSGraph& graph);
+
+ public:
+ PTScotchPartitioner() = delete;
+};
+
+#endif // PT_SCOTCH_PARTITIONER_HPP
diff --git a/src/utils/ParMETISPartitioner.cpp b/src/utils/ParMETISPartitioner.cpp
index 93018f44e10f94f5d88f2987e618336caf494f27..47864de1fd3337bc6e193ad3453ad8d6c75eb797 100644
--- a/src/utils/ParMETISPartitioner.cpp
+++ b/src/utils/ParMETISPartitioner.cpp
@@ -18,16 +18,6 @@ ParMETISPartitioner::partition(const CRSGraph& graph)
std::cout << "Partitioning graph into " << rang::style::bold << parallel::size() << rang::style::reset
<< " parts using " << rang::fgB::green << "ParMETIS" << rang::fg::reset << '\n';
- int wgtflag = 0;
- int numflag = 0;
- int ncon = 1;
- int npart = parallel::size();
- std::vector<float> tpwgts(npart, 1. / npart);
-
- std::vector<float> ubvec{1.05};
- std::vector<int> options{1, 0, 0};
- int edgecut = 0;
-
MPI_Group world_group;
MPI_Comm_group(parallel::Messenger::getInstance().comm(), &world_group);
@@ -46,13 +36,23 @@ ParMETISPartitioner::partition(const CRSGraph& graph)
MPI_Group_incl(world_group, group_ranks.size(), &(group_ranks[0]), &mesh_group);
- MPI_Comm parmetis_comm;
- MPI_Comm_create_group(parallel::Messenger::getInstance().comm(), mesh_group, 1, &parmetis_comm);
-
- int local_number_of_nodes = graph.numberOfNodes();
+ MPI_Comm partitioning_comm;
+ MPI_Comm_create_group(parallel::Messenger::getInstance().comm(), mesh_group, 1, &partitioning_comm);
Array<int> partition;
if (graph.numberOfNodes() > 0) {
+ int wgtflag = 0;
+ int numflag = 0;
+ int ncon = 1;
+ int npart = parallel::size();
+ std::vector<float> tpwgts(npart, 1. / npart);
+
+ std::vector<float> ubvec{1.05};
+ std::vector<int> options{1, 0, 0};
+ int edgecut = 0;
+
+ int local_number_of_nodes = graph.numberOfNodes();
+
partition = Array<int>(local_number_of_nodes);
std::vector<int> vtxdist{0, local_number_of_nodes};
@@ -64,16 +64,15 @@ ParMETISPartitioner::partition(const CRSGraph& graph)
int result =
ParMETIS_V3_PartKway(&(vtxdist[0]), entries_ptr, neighbors_ptr, NULL, NULL, &wgtflag, &numflag, &ncon, &npart,
- &(tpwgts[0]), &(ubvec[0]), &(options[0]), &edgecut, &(partition[0]), &parmetis_comm);
+ &(tpwgts[0]), &(ubvec[0]), &(options[0]), &edgecut, &(partition[0]), &partitioning_comm);
// LCOV_EXCL_START
if (result == METIS_ERROR) {
throw UnexpectedError("Metis Error");
}
// LCOV_EXCL_STOP
-
- MPI_Comm_free(&parmetis_comm);
}
+ MPI_Comm_free(&partitioning_comm);
MPI_Group_free(&mesh_group);
MPI_Group_free(&world_group);
diff --git a/src/utils/Partitioner.cpp b/src/utils/Partitioner.cpp
index 4c7145cf247c3e67bb5e2df802cf4c64e2050d66..4f53d322f5e52c130122ccc3966270e7220d34d7 100644
--- a/src/utils/Partitioner.cpp
+++ b/src/utils/Partitioner.cpp
@@ -1,5 +1,6 @@
#include <utils/Partitioner.hpp>
+#include <utils/PTScotchPartitioner.hpp>
#include <utils/ParMETISPartitioner.hpp>
Partitioner::Partitioner(const PartitionerOptions& options) : m_partitioner_options{options} {}
@@ -12,7 +13,7 @@ Partitioner::partition(const CRSGraph& graph)
return ParMETISPartitioner::partition(graph);
}
case PartitionerLibrary::ptscotch: {
- throw NotImplementedError("PTScotch");
+ return PTScotchPartitioner::partition(graph);
}
default: {
throw UnexpectedError("invalid partition library");