Experiment parallel communication to dispatch read mesh

src/mesh/GmshReader.cpp

@@ -15,6 +15,8 @@
 #include <Messenger.hpp>
 #include <Partitioner.hpp>
 
+#include <ArrayUtils.hpp>
+
 #include <map>
 #include <regex>
 #include <iomanip>
@@ -175,7 +177,52 @@ void GmshReader::_dispatch()
   pout() << "Mesh read by process " << rang::style::bold << reader_rank << rang::style::reset << '\n';
 
   Partitioner P;
-  Array<int> cell_new_owner = broadcast(P.partition(mesh_graph), reader_rank);
+  Array<int> cell_new_owner = P.partition(mesh_graph);
+
+  Array<int> nb_cell_to_send_by_proc(commSize());
+  for (size_t i=0; i<cell_new_owner.size(); ++i) {
+    nb_cell_to_send_by_proc[cell_new_owner[i]]++;
+  }
+
+  // for (int i_rank=0; i_rank<commSize(); ++i_rank) {
+  //   if (commRank() == i_rank) {
+  //     for (size_t i_recv=0; i_recv<commSize(); ++i_recv) {
+  //       std::cout << commRank()
+  //                 << " gives " << nb_cell_to_send_by_proc[i_recv]
+  //                 << " cells to " << i_recv << '\n' << std::flush;
+  //     }
+  //   }
+  //   barrier();
+  // }
+  Array<int> nb_cell_to_recv_by_proc = allToAll(nb_cell_to_send_by_proc);
+
+  // for (int i_rank=0; i_rank<commSize(); ++i_rank) {
+  //   if (commRank() == i_rank) {
+  //     for (size_t i_send=0; i_send<commSize(); ++i_send) {
+  //       std::cout << commRank()
+  //               << " recv " << nb_cell_to_recv_by_proc[i_send]
+  //               << " cells of " << i_send << '\n';
+  //     }
+  //   }
+  //   barrier();
+  // }
+  const size_t cell_number = mesh.numberOfCells();
+  const size_t new_cell_number
+      = cell_number
+      + Sum(nb_cell_to_recv_by_proc)
+      - Sum(nb_cell_to_send_by_proc);
+
+  std::cout << commRank() << ": " << cell_number << " -> " << new_cell_number << " cells\n";
+
+  // now share owner table
+  cell_new_owner = broadcast(cell_new_owner, reader_rank);
+
+  Array<int> cell_new_owner_nb_cell(commSize());
+  cell_new_owner_nb_cell.fill(0);
+  for (size_t i=0; i<cell_new_owner.size(); ++i) {
+    cell_new_owner_nb_cell[cell_new_owner[i]]++;
+  }
+
 
   Array<int> node_new_owner(mesh.numberOfNodes());
   if (commRank() == reader_rank) {
@@ -197,17 +244,15 @@ void GmshReader::_dispatch()
 
   for (int i_rank=0; i_rank<commSize(); ++i_rank) {
     if (commRank() == i_rank) {
-      size_t cpt=0;
       std::cout << i_rank << " cells -> ";
       for (size_t i=0; i<cell_new_owner.size(); ++i) {
         if (commRank() == cell_new_owner[i]) {
           std::cout << i << ' ';
-          cpt++;
         }
       }
-      std::cout << " [" << cpt << "]\n" << std::flush;
+      std::cout << " [" << cell_new_owner_nb_cell[i_rank] << "]\n" << std::flush;
     }
-    barrier();
+    //    barrier();
   }
 
   for (int i_rank=0; i_rank<commSize(); ++i_rank) {
@@ -222,7 +267,20 @@ void GmshReader::_dispatch()
       }
       std::cout << " [" << cpt << "]\n" << std::flush;
     }
-    barrier();
+    //    barrier();
+  }
+
+  for (int i_rank=0; i_rank<commSize(); ++i_rank) {
+    if (commRank() == i_rank) {
+      const auto cell_type
+          = mesh.connectivity().cellType();
+      std::cout << i_rank << " cell_type -> ";
+      for (CellId j=0; j<cell_type.size(); ++j) {
+        std::cout << static_cast<int>(cell_type[j]) << ' ';
+      }
+      std::cout << '\n';
+    }
+    //    barrier();
   }
 
   Messenger::destroy();