improved console output

cellular_automaton/wireworld_c/configuration.c

@@ -152,7 +152,12 @@ int info_enabled(const conf_t *c)
 
 int debug_enabled(const conf_t *c)
 {
-   return log_enabled(c, DEBUG);
+   static int rank = -1;
+   if(rank < 0) {
+      MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+   }
+
+   return log_enabled(c, DEBUG) && rank == 0;
 }
 
 int trace_enabled(const conf_t *c)

cellular_automaton/wireworld_c/main.c

@@ -13,6 +13,8 @@ void broadcast_configuration(conf_t *c);
 
 void read_input(const conf_t *c, world_t *world);
 
+void create_cart_comm(const conf_t *c, MPI_Comm *cart_comm);
+
 void iterate(const conf_t *c, world_t *world);
 
 void print_avg_timings(const conf_t *c, double total_time, double sim_time, double io_time);
@@ -67,8 +69,6 @@ void broadcast_configuration(conf_t *c) {
 
 void read_input(const conf_t *c, world_t *world) {
    int rank;
-   const int periods[2] = {0}; // non-periodic boundaries
-   const int allow_reorder = 1;
    MPI_Comm cart_comm;
 
    char input_filename[FILE_NAME_SZ];
@@ -88,31 +88,50 @@ void read_input(const conf_t *c, world_t *world) {
    // Read header
    file_read_header(file, global_sizes, &header_length);
 
-   if(info_enabled(c)) printf(
+   if(debug_enabled(c)) printf(
       "Read header (%ld characters).\n"
       "Global size: %ld x %ld\n\n",
       header_length, global_sizes[0], global_sizes[1]
    );
    // Initialize cells (determine local tile, allocate memory)
-   MPI_Cart_create(MPI_COMM_WORLD, 2, c->nprocs, periods, allow_reorder, &cart_comm);
+   create_cart_comm(c, &cart_comm);
    world_init(world, cart_comm, global_sizes, c);
    MPI_Comm_free(&cart_comm);
 
-   if(debug_enabled(c)) printf(
-      "%03d: Local tile: [%ld %ld) x [%ld %ld)\n", rank,
-      world->local_start[0], world->local_start[0]+world->local_size[0],
-      world->local_start[1], world->local_start[1]+world->local_size[1]
-   );
-
    // Collectively read cell data
    file_read_world(file, world, header_length);
    MPI_File_close(&file);
 }
 
+void create_cart_comm(const conf_t *c, MPI_Comm *cart_comm)
+{
+   const int periods[] = {0, 0}; // non-periodic boundaries
+
+   const int allow_reorder = 1;
+   int comm_world_rank, new_rank;
+   int local_ranks_different, ranks_reordered;
+
+   if(debug_enabled(c)) printf("Creating Cartesian communicator...\n");
+   MPI_Cart_create(MPI_COMM_WORLD, 2, c->nprocs, periods, allow_reorder, cart_comm);
+
+   MPI_Comm_rank(MPI_COMM_WORLD, &comm_world_rank);
+   MPI_Comm_rank(*cart_comm, &new_rank);
+
+   local_ranks_different = comm_world_rank != new_rank;
+   MPI_Allreduce(
+      &local_ranks_different, &ranks_reordered, 1, MPI_INT,
+      MPI_LOR, MPI_COMM_WORLD
+   );
+
+   if(debug_enabled(c)) printf(
+       "INFO: MPI reordered ranks: %s\n", ranks_reordered ? "YES" : "NO"
+   );
+}
+
 void iterate(const conf_t *c, world_t *world)
 {
-   const size_t n_it = c->n_iterations;
-   const size_t n_gen = c->n_generations_per_iteration;
+   const int  n_it  = c->n_iterations;
+   const long n_gen = c->n_generations_per_iteration;
 
    size_t i, g;
    double total_time, sim_time = 0, io_time = 0;

cellular_automaton/wireworld_c/mpitypes.c

@@ -20,9 +20,9 @@ void mpitype_conf_init(MPI_Datatype *new_type)
    MPI_Get_address(&dummy.CONF_T_FIRST_LONG_MEMBER, &displacements[1]);
    MPI_Get_address(&dummy.CONF_T_FIRST_CHAR_MEMBER, &displacements[2]);
 
-   for(i = 0; i < 2; i++) displacements[i] -= base;
+   for(i = 0; i < 3; i++) displacements[i] -= base;
 
-   MPI_Type_create_struct(2, blocklengths, displacements, types, new_type);
+   MPI_Type_create_struct(3, blocklengths, displacements, types, new_type);
    MPI_Type_commit(new_type);
 }
 

cellular_automaton/wireworld_c/world.c

@@ -39,6 +39,16 @@ void world_init(world_t *world, MPI_Comm cart_comm, size_t *global_size, const c
    world_init_io_type(world);
    world_init_neighborhood(world, cart_comm, nprocs, proc_coord, c);
    world_init_persistent_requests(world, c);
+
+   if(trace_enabled(c)) {
+      int rank;
+      MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+      printf(
+         "%03d: Local tile: [%ld %ld) x [%ld %ld)\n", rank,
+         world->local_start[0], world->local_start[0]+world->local_size[0],
+         world->local_start[1], world->local_start[1]+world->local_size[1]
+      );
+   }
 }
 
 void world_free(world_t *world)
@@ -143,6 +153,8 @@ void world_init_neighborhood(world_t *world, MPI_Comm cart_comm, int nprocs[], i
 
    if(c->transmission_mode == SPARSE_COLLECTIVE) {
       const int allow_reorder = 0;
+
+      if(debug_enabled(c)) printf("Creating MPI distributed graph communicator...\n");
       MPI_Dist_graph_create_adjacent(cart_comm,
          n, neighbor_ranks, weights,
          n, neighbor_ranks, weights,
@@ -182,6 +194,8 @@ void world_init_persistent_requests(world_t *world, const conf_t *c)
 
       MPI_Comm comm = world->transfer.comm;
 
+      if(debug_enabled(c)) printf("Initializing persistent requests...\n");
+
       for(i = 0; i < n_neighbors; i++) {
          MPI_Send_init(
             world->cells_prev, 1, send_types[i], neighbor_ranks[i],
@@ -215,7 +229,7 @@ void world_free_persistent_requests(world_t *world)
 
 size_t world_get_storage_size(const world_t *world)
 {
-   const size_t nx = world->local_size[0], 
+   const size_t nx = world->local_size[0],
                 ny = world->local_size[1];
    return (nx+2)*(ny+2)*sizeof(char);
 }