Add recv and send data to particle cache

This adds teh recv and send data to the particle cache in order
to prevent dynamic reallocation of this vector, whose size is not
changing anyway. This can significantly (10%) increase performance
in some of our applications

diff --git a/include/deal.II/particles/partitioner.h b/include/deal.II/particles/partitioner.h
index 46ee1def562326f374a85633bb2e6b21a66f9564..f4361a3ae1fe6438da5f370c1c986d767a484821 100644 (file)
--- a/include/deal.II/particles/partitioner.h
+++ b/include/deal.II/particles/partitioner.h
@@ -97,6 +97,18 @@ namespace Particles
       std::vector<typename std::multimap<internal::LevelInd,
                                          Particle<dim, spacedim>>::iterator>
         ghost_particles_iterators;
+
+      /**
+       * Vector of char that is used to organize the particle information to be
+       * sent to other processors
+       */
+      std::vector<char> send_data;
+
+      /**
+       * Vector of char that is used to organize the particle information to
+       * received from other processors
+       */
+      std::vector<char> recv_data;
     };
   } // namespace internal
 

diff --git a/source/particles/particle_handler.cc b/source/particles/particle_handler.cc
index b135d69a4a2106411229740b1a3967d449e0cafd..4926f52ce33eb6aeb1619ec8a30fbe21b2ba2598 100644 (file)
--- a/source/particles/particle_handler.cc
+++ b/source/particles/particle_handler.cc
@@ -1521,6 +1521,11 @@ namespace Particles
             n_recv_data[i] * individual_particle_data_size;
 
         ghost_particles_cache.neighbors = neighbors;
+
+        ghost_particles_cache.send_data.resize(
+          ghost_particles_cache.send_pointers.back());
+        ghost_particles_cache.recv_data.resize(
+          ghost_particles_cache.recv_pointers.back());
       }
 
     while (reinterpret_cast<std::size_t>(recv_data_it) -
@@ -1580,13 +1585,11 @@ namespace Particles
       ExcMessage(
         "This function is only implemented for parallel::TriangulationBase objects."));
 
-    std::vector<char> send_data;
+    std::vector<char> &send_data = ghost_particles_cache.send_data;
 
     // Fill data to send
     if (send_pointers.back() > 0)
       {
-        // Allocate space for sending particle data
-        send_data.resize(send_pointers.back());
         void *data = static_cast<void *>(&send_data.front());
 
         // Serialize the data sorted by receiving process
@@ -1599,8 +1602,7 @@ namespace Particles
             }
       }
 
-    // Set up the space for the received particle data
-    std::vector<char> recv_data(recv_pointers.back());
+    std::vector<char> &recv_data = ghost_particles_cache.recv_data;
 
     // Exchange the particle data between domains
     {