X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/9bfc53cc59cae28067100a5c8b377d64f6b95a8d..d873c22327ce06f75a6c6d48ffd84d96e4fd77e0:/examples/gras/pmm/pmm.c

diff --git a/examples/gras/pmm/pmm.c b/examples/gras/pmm/pmm.c
old mode 100755
new mode 100644
index 101ab30c06..7e7d35d32d
--- a/examples/gras/pmm/pmm.c
+++ b/examples/gras/pmm/pmm.c
@@ -1,9 +1,7 @@
-/* $Id$ */
 /* pmm - parallel matrix multiplication "double diffusion"                  */
 
-/* Copyright (c) 2006 Ahmed Harbaoui.                                       */
-/* Copyright (c) 2006 Martin Quinson.                                       */
-/* All rights reserved.                                                     */
+/* Copyright (c) 2006, 2007, 2008, 2009, 2010. The SimGrid Team.
+ * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
@@ -12,43 +10,45 @@
 #include "xbt/matrix.h"
 #include "amok/peermanagement.h"
 
-#define PROC_MATRIX_SIZE 3
+#define PROC_MATRIX_SIZE 2
 #define NEIGHBOR_COUNT PROC_MATRIX_SIZE - 1
 #define SLAVE_COUNT (PROC_MATRIX_SIZE*PROC_MATRIX_SIZE)
 
-#define DATA_MATRIX_SIZE 9
-const int submatrix_size = DATA_MATRIX_SIZE/PROC_MATRIX_SIZE;
+#define DATA_MATRIX_SIZE 18
+const int submatrix_size = DATA_MATRIX_SIZE / PROC_MATRIX_SIZE;
 
-XBT_LOG_NEW_DEFAULT_CATEGORY(pmm,"Parallel Matrix Multiplication");
+XBT_LOG_NEW_DEFAULT_CATEGORY(pmm, "Parallel Matrix Multiplication");
 
 /* struct for recovering results */
-GRAS_DEFINE_TYPE(s_result,struct s_result {
-  int linepos;
-  int rowpos;
-  xbt_matrix_t C GRAS_ANNOTE(subtype,double);
-});
+GRAS_DEFINE_TYPE(s_result, struct s_result {
+                 int linepos; int rowpos;
+                 xbt_matrix_t C GRAS_ANNOTE(subtype, double);
+                 });
+
 typedef struct s_result result_t;
 
 /* struct to send initial data to slave */
-GRAS_DEFINE_TYPE(s_pmm_assignment,struct s_pmm_assignment {
-  int linepos;
-  int rowpos;
-  xbt_peer_t line[NEIGHBOR_COUNT];
-  xbt_peer_t row[NEIGHBOR_COUNT];
-  xbt_matrix_t A GRAS_ANNOTE(subtype,double);
-  xbt_matrix_t B GRAS_ANNOTE(subtype,double);
-});
+GRAS_DEFINE_TYPE(s_pmm_assignment, struct s_pmm_assignment {
+                 int linepos;
+                 int rowpos;
+                 xbt_peer_t line[NEIGHBOR_COUNT];
+                 xbt_peer_t row[NEIGHBOR_COUNT];
+                 xbt_matrix_t A GRAS_ANNOTE(subtype, double);
+                 xbt_matrix_t B GRAS_ANNOTE(subtype, double);
+                 });
+
 typedef struct s_pmm_assignment s_pmm_assignment_t;
 
 /* register messages which may be sent (common to client and server) */
-static void register_messages(void) {
+static void register_messages(void)
+{
   gras_datadesc_type_t result_type;
   gras_datadesc_type_t pmm_assignment_type;
 
-  gras_datadesc_set_const("NEIGHBOR_COUNT",NEIGHBOR_COUNT);
-  result_type=gras_datadesc_by_symbol(s_result);
-  pmm_assignment_type=gras_datadesc_by_symbol(s_pmm_assignment);
-	
+  gras_datadesc_set_const("NEIGHBOR_COUNT", NEIGHBOR_COUNT);
+  result_type = gras_datadesc_by_symbol(s_result);
+  pmm_assignment_type = gras_datadesc_by_symbol(s_pmm_assignment);
+
   /* receive a final result from slave */
   gras_msgtype_declare("result", result_type);
 
@@ -56,13 +56,20 @@ static void register_messages(void) {
   gras_msgtype_declare("pmm_slave", pmm_assignment_type);
 
   /* send data between slaves */
-  gras_msgtype_declare("dataA", gras_datadesc_matrix(gras_datadesc_by_name("double"),NULL));
-  gras_msgtype_declare("dataB", gras_datadesc_matrix(gras_datadesc_by_name("double"),NULL));
+  gras_msgtype_declare("dataA",
+                       gras_datadesc_matrix(gras_datadesc_by_name
+                                            ("double"), NULL));
+  gras_msgtype_declare("dataB",
+                       gras_datadesc_matrix(gras_datadesc_by_name
+                                            ("double"), NULL));
+
+  /* synchronization message */
+  gras_msgtype_declare("pmm_sync", 0);
 }
 
 /* Function prototypes */
-int slave (int argc,char *argv[]);
-int master (int argc,char *argv[]);
+int slave(int argc, char *argv[]);
+int master(int argc, char *argv[]);
 
 
 /* **********************************************************************
@@ -71,276 +78,285 @@ int master (int argc,char *argv[]);
 
 /* Global private data */
 typedef struct {
-  int nbr_row,nbr_line;
+  int nbr_row, nbr_line;
   int remaining_step;
   int remaining_ack;
 } master_data_t;
 
-
-int master (int argc,char *argv[]) {
+int master(int argc, char *argv[])
+{
 
   int i;
-  double init_delay;
 
-  xbt_matrix_t A,B,C;
+  xbt_matrix_t A, B, C;
   result_t result;
 
   gras_socket_t from;
 
-  xbt_dynar_t peers; /* group of slaves */
+  xbt_dynar_t peers;            /* group of slaves */
   xbt_peer_t grid[SLAVE_COUNT]; /* The slaves as an array */
-  gras_socket_t socket[SLAVE_COUNT]; /* sockets for brodcast to slaves */
+  gras_socket_t socket[SLAVE_COUNT];    /* sockets for brodcast to slaves */
 
   /* Init the GRAS's infrastructure */
   gras_init(&argc, argv);
   amok_pm_init();
   register_messages();
-      
+
   /* Initialize data matrices */
-  A = xbt_matrix_double_new_id(DATA_MATRIX_SIZE,DATA_MATRIX_SIZE);
-  B = xbt_matrix_double_new_seq(DATA_MATRIX_SIZE,DATA_MATRIX_SIZE);
-  C = xbt_matrix_double_new_zeros(DATA_MATRIX_SIZE,DATA_MATRIX_SIZE);
-	
+  A = xbt_matrix_double_new_id(DATA_MATRIX_SIZE, DATA_MATRIX_SIZE);
+  B = xbt_matrix_double_new_seq(DATA_MATRIX_SIZE, DATA_MATRIX_SIZE);
+  C = xbt_matrix_double_new_zeros(DATA_MATRIX_SIZE, DATA_MATRIX_SIZE);
+
   /* Create the connexions */
-  xbt_assert0(argc>1, "Usage: master <port>");
+  xbt_assert0(argc > 1, "Usage: master <port>");
   gras_socket_server(atoi(argv[1]));
-  peers=amok_pm_group_new("pmm");
-   
+  peers = amok_pm_group_new("pmm");
+
   /* friends, we're ready. Come and play */
-  if (gras_if_RL()) {
-     init_delay = 5;
-  } else {
-     init_delay = 15; /* no idea why I have to wait that long in simulation */
-  }
-  INFO1("Wait for peers for %.0f sec",init_delay);
-  gras_msg_handleall(init_delay);
-  INFO1("Got %ld pals",xbt_dynar_length(peers));
-
-  for (i=0;
-       i<xbt_dynar_length(peers) && i<SLAVE_COUNT;
-       i++) {
-
-    xbt_dynar_get_cpy(peers,i,&grid[i]);
-    INFO2("Connecting to %s:%d.",grid[i]->name,grid[i]->port);
-    socket[i]=gras_socket_client(grid[i]->name,grid[i]->port);
-    INFO2("Connected to %s:%d.",grid[i]->name,grid[i]->port);
+  INFO0("Wait for peers for 2 sec");
+  gras_msg_handleall(2);
+  do {
+    INFO2("Got only %ld pals (of %d). Wait 2 more seconds",
+        xbt_dynar_length(peers),SLAVE_COUNT);
+    gras_msg_handleall(2);
+  } while (xbt_dynar_length(peers) < SLAVE_COUNT);
+  INFO1("Good. Got %ld pals", xbt_dynar_length(peers));
+
+  for (i = 0; i < xbt_dynar_length(peers) && i < SLAVE_COUNT; i++) {
+    xbt_dynar_get_cpy(peers, i, &grid[i]);
+    socket[i] = gras_socket_client(grid[i]->name, grid[i]->port);
   }
-  xbt_assert2(i==SLAVE_COUNT,
-	      "Not enough slaves for this setting (got %d of %d). Change the deployment file",
-	      i,SLAVE_COUNT);
+  xbt_assert2(i == SLAVE_COUNT,
+              "Not enough slaves for this setting (got %d of %d). Change the deployment file",
+              i, SLAVE_COUNT);
 
   /* Kill surnumerous slaves */
-  for (i=SLAVE_COUNT; i<xbt_dynar_length(peers); ) {
+  for (i = SLAVE_COUNT; i < xbt_dynar_length(peers);) {
     xbt_peer_t h;
 
-    xbt_dynar_remove_at(peers,i,&h);
+    xbt_dynar_remove_at(peers, i, &h);
     INFO2("Too much slaves. Killing %s:%d", h->name, h->port);
-    amok_pm_kill_hp(h->name,h->port);
+    amok_pm_kill_hp(h->name, h->port);
     free(h);
   }
 
 
   /* Assign job to slaves */
-  int row=0, line=0;
+  int row = 0, line = 0;
   INFO0("XXXXXXXXXXXXXXXXXXXXXX begin Multiplication");
-  for(i=0 ; i<SLAVE_COUNT; i++){
+  for (i = 0; i < SLAVE_COUNT; i++) {
     s_pmm_assignment_t assignment;
-    int j,k;
+    int j, k;
 
-    assignment.linepos=line; // assigned line
-    assignment.rowpos=row;   // assigned row
+    assignment.linepos = line;  // assigned line
+    assignment.rowpos = row;    // assigned row
 
     /* Neiborhood */
-    for (j=0,k=0; j<PROC_MATRIX_SIZE; j++) {
-      if (i != j*PROC_MATRIX_SIZE+(row)) {	    
-	 assignment.row[k] = grid[ j*PROC_MATRIX_SIZE+(row) ] ;
-	 k++;
+    for (j = 0, k = 0; j < PROC_MATRIX_SIZE; j++) {
+      if (i != j * PROC_MATRIX_SIZE + (row)) {
+        assignment.row[k] = grid[j * PROC_MATRIX_SIZE + (row)];
+        k++;
       }
     }
-    for (j=0,k=0; j<PROC_MATRIX_SIZE; j++) {
-      if (i != (line)*PROC_MATRIX_SIZE+j) {	    
-	 assignment.line[k] =  grid[ (line)*PROC_MATRIX_SIZE+j ] ;
-	 k++;
+    for (j = 0, k = 0; j < PROC_MATRIX_SIZE; j++) {
+      if (i != (line) * PROC_MATRIX_SIZE + j) {
+        assignment.line[k] = grid[(line) * PROC_MATRIX_SIZE + j];
+        k++;
       }
     }
 
-    assignment.A=xbt_matrix_new_sub(A,
-				    submatrix_size,submatrix_size,
-				    submatrix_size*line,submatrix_size*row,
-				    NULL);
-    assignment.B=xbt_matrix_new_sub(B,
-				    submatrix_size,submatrix_size,
-				    submatrix_size*line,submatrix_size*row,
-				    NULL);
+    assignment.A = xbt_matrix_new_sub(A,
+                                      submatrix_size, submatrix_size,
+                                      submatrix_size * line,
+                                      submatrix_size * row, NULL);
+    assignment.B =
+        xbt_matrix_new_sub(B, submatrix_size, submatrix_size,
+                           submatrix_size * line, submatrix_size * row,
+                           NULL);
     row++;
     if (row >= PROC_MATRIX_SIZE) {
-      row=0;
+      row = 0;
       line++;
     }
-		
-    gras_msg_send(socket[i],gras_msgtype_by_name("pmm_slave"),&assignment);
+
+    gras_msg_send(socket[i], "pmm_slave", &assignment);
     xbt_matrix_free(assignment.A);
     xbt_matrix_free(assignment.B);
   }
 
-  /* (have a rest while the slave perform the multiplication) */
+  /* synchronize slaves */
+  for (i = 0; i < PROC_MATRIX_SIZE; i++) {
+    int j;
+    for (j = 0; j < SLAVE_COUNT; j++)
+      gras_msg_wait(600, "pmm_sync", NULL, NULL);
+    for (j = 0; j < SLAVE_COUNT; j++)
+      gras_msg_send(socket[j], "pmm_sync", NULL);
+  }
 
   /* Retrieve the results */
-  for( i=0;i< SLAVE_COUNT;i++){
-    gras_msg_wait(6000,gras_msgtype_by_name("result"),&from,&result);
-    VERB2("%d slaves are done already. Waiting for %d",i+1, SLAVE_COUNT);
-    xbt_matrix_copy_values(C,result.C,   submatrix_size,submatrix_size,
-			   submatrix_size*result.linepos,
-			   submatrix_size*result.rowpos,
-			   0,0,NULL);
+  for (i = 0; i < SLAVE_COUNT; i++) {
+    gras_msg_wait(6000, "result", &from, &result);
+    VERB2("%d slaves are done already. Waiting for %d", i + 1,
+          SLAVE_COUNT);
+    xbt_matrix_copy_values(C, result.C, submatrix_size, submatrix_size,
+                           submatrix_size * result.linepos,
+                           submatrix_size * result.rowpos, 0, 0, NULL);
     xbt_matrix_free(result.C);
   }
   /*    end of gather   */
 
-  if (DATA_MATRIX_SIZE < 30) {
-     INFO0 ("The Result of Multiplication is :");
-     xbt_matrix_dump(C,"C:res",0,xbt_matrix_dump_display_double);
-  } else {
-     INFO1("Matrix size too big (%d>30) to be displayed here",DATA_MATRIX_SIZE);
+  if (xbt_matrix_double_is_seq(C))
+    INFO0("XXXXXXXXXXXXXXXXXXXXXX Ok, the result matches expectations");
+  else {
+    WARN0("the result seems wrong");
+    if (DATA_MATRIX_SIZE < 30) {
+      INFO0("The Result of Multiplication is :");
+      xbt_matrix_dump(C, "C:res", 0, xbt_matrix_dump_display_double);
+    } else {
+      INFO1("Matrix size too big (%d>30) to be displayed here",
+            DATA_MATRIX_SIZE);
+    }
   }
 
-  amok_pm_group_shutdown ("pmm");   /* Ok, we're out of here */
+  amok_pm_group_shutdown("pmm");        /* Ok, we're out of here */
+
+  for (i = 0; i < SLAVE_COUNT; i++)
+    gras_socket_close(socket[i]);
 
-  for(i=0; i<SLAVE_COUNT; i++) {
-     gras_socket_close(socket[i]);
-  }
-   
   xbt_matrix_free(A);
   xbt_matrix_free(B);
   xbt_matrix_free(C);
   gras_exit();
   return 0;
-} /* end_of_master */
+}                               /* end_of_master */
 
 /* **********************************************************************
  * slave code
  * **********************************************************************/
 
-static int pmm_worker_cb(gras_msg_cb_ctx_t ctx, void *payload) {
-  /* Recover my initialized Data and My Position*/
-  s_pmm_assignment_t assignment = *(s_pmm_assignment_t*)payload;
+static int pmm_worker_cb(gras_msg_cb_ctx_t ctx, void *payload)
+{
+  /* Recover my initialized Data and My Position */
+  s_pmm_assignment_t assignment = *(s_pmm_assignment_t *) payload;
   gras_socket_t master = gras_msg_cb_ctx_from(ctx);
 
-  xbt_ex_t e; 
+  xbt_ex_t e;
 
-  int step,l;
-  xbt_matrix_t bA=xbt_matrix_new(submatrix_size,submatrix_size,
-				 sizeof(double),NULL);
-  xbt_matrix_t bB=xbt_matrix_new(submatrix_size,submatrix_size,
-				 sizeof(double),NULL);
+  int step, l;
+  xbt_matrix_t bA = xbt_matrix_new(submatrix_size, submatrix_size,
+                                   sizeof(double), NULL);
+  xbt_matrix_t bB = xbt_matrix_new(submatrix_size, submatrix_size,
+                                   sizeof(double), NULL);
+
+  int myline, myrow;
+  xbt_matrix_t mydataA, mydataB;
+  xbt_matrix_t bC =
+      xbt_matrix_double_new_zeros(submatrix_size, submatrix_size);
 
-  int myline,myrow;
-  xbt_matrix_t mydataA,mydataB;
-  xbt_matrix_t bC=xbt_matrix_double_new_zeros(submatrix_size,submatrix_size);
-  
   result_t result;
- 
-  gras_socket_t from;  /* to exchange data with my neighbor */
+
+  gras_socket_t from;           /* to exchange data with my neighbor */
 
   /* sockets for brodcast to other slave */
-  gras_socket_t socket_line[PROC_MATRIX_SIZE-1];
-  gras_socket_t socket_row[PROC_MATRIX_SIZE-1];
-  memset(socket_line,0,sizeof(socket_line));
-  memset(socket_row,0,sizeof(socket_row));
-   
+  gras_socket_t socket_line[PROC_MATRIX_SIZE - 1];
+  gras_socket_t socket_row[PROC_MATRIX_SIZE - 1];
+  memset(socket_line, 0, sizeof(socket_line));
+  memset(socket_row, 0, sizeof(socket_row));
+
   int i;
 
-  gras_os_sleep(1); /* wait for my pals */
+  gras_os_sleep(1);             /* wait for my pals */
 
-  myline  = assignment.linepos;
-  myrow   = assignment.rowpos;
+  myline = assignment.linepos;
+  myrow = assignment.rowpos;
   mydataA = assignment.A;
   mydataB = assignment.B;
 
-  INFO2("Receive my pos (%d,%d) and assignment",myline,myrow);
+  if (gras_if_RL())
+    INFO0("Receive my pos and assignment");
+  else
+    INFO2("Receive my pos (%d,%d) and assignment", myline, myrow);
 
   /* Get my neighborhood from the assignment message (skipping myself) */
-  for (i=0 ; i<PROC_MATRIX_SIZE-1 ; i++){
-    socket_line[i]=gras_socket_client(assignment.line[i]->name,
-				      assignment.line[i]->port);
+  for (i = 0; i < PROC_MATRIX_SIZE - 1; i++) {
+    socket_line[i] = gras_socket_client(assignment.line[i]->name,
+                                        assignment.line[i]->port);
     xbt_peer_free(assignment.line[i]);
   }
-  for (i=0 ; i<PROC_MATRIX_SIZE-1 ; i++){
-    socket_row[i]=gras_socket_client(assignment.row[i]->name,
-				     assignment.row[i]->port);
-    xbt_peer_free(assignment.row[i]);    
+  for (i = 0; i < PROC_MATRIX_SIZE - 1; i++) {
+    socket_row[i] = gras_socket_client(assignment.row[i]->name,
+                                       assignment.row[i]->port);
+    xbt_peer_free(assignment.row[i]);
   }
 
-  for (step=0; step<PROC_MATRIX_SIZE;step++) {
-	
+  for (step = 0; step < PROC_MATRIX_SIZE; step++) {
+    gras_msg_send(master, "pmm_sync", NULL);
+    gras_msg_wait(600, "pmm_sync", NULL, NULL);
+
     /* a line brodcast */
-    if(myline==step){
-       INFO3("LINE: step(%d) = Myline(%d). Broadcast my data (myport=%d).",
-	     step,myline,gras_os_myport());
-       for (l=0;l < PROC_MATRIX_SIZE-1 ;l++) {
-	  INFO2("LINE:   Send to %s:%d",
-		gras_socket_peer_name(socket_row[l]),
-		gras_socket_peer_port(socket_row[l]));
-	 gras_msg_send(socket_row[l], 
-		       gras_msgtype_by_name("dataB"), 
-		       &mydataB);
-       }
-       
-	
-       xbt_matrix_free(bB);
-       bB = xbt_matrix_new_sub(mydataB,
-			       submatrix_size,submatrix_size,
-			       0,0,NULL);	
+    if (myline == step) {
+      VERB2("LINE: step(%d) = Myline(%d). Broadcast my data.", step,
+            myline);
+      for (l = 0; l < PROC_MATRIX_SIZE - 1; l++) {
+        VERB1("LINE:   Send to %s", gras_socket_peer_name(socket_row[l]));
+        gras_msg_send(socket_row[l], "dataB", &mydataB);
+      }
+
+
+      xbt_matrix_free(bB);
+      bB = xbt_matrix_new_sub(mydataB,
+                              submatrix_size, submatrix_size, 0, 0, NULL);
     } else {
       TRY {
-	xbt_matrix_free(bB);
-	gras_msg_wait(600,gras_msgtype_by_name("dataB"),&from,&bB);
-      } CATCH(e) {
-	RETHROW0("Can't get a data message from line : %s");
+        xbt_matrix_free(bB);
+        gras_msg_wait(600, "dataB", &from, &bB);
+      }
+      CATCH(e) {
+        RETHROW0("Can't get a data message from line : %s");
       }
-      INFO4("LINE: step(%d) <> Myline(%d). Receive data from %s:%d",step,myline,
-	    gras_socket_peer_name(from), gras_socket_peer_port(from));
+      VERB3("LINE: step(%d) <> Myline(%d). Receive data from %s", step,
+            myline, gras_socket_peer_name(from));
     }
 
     /* a row brodcast */
-    if (myrow==step) { 
-       INFO2("ROW: step(%d)=myrow(%d). Broadcast my data",step,myrow);
-       for (l=1;l < PROC_MATRIX_SIZE ; l++) {
-	  INFO2("ROW:   Send to %s:%d",
-		gras_socket_peer_name(socket_line[l-1]),
-		gras_socket_peer_port(socket_line[l-1]));
-	  gras_msg_send(socket_line[l-1],gras_msgtype_by_name("dataA"), &mydataA);
-       }
-       xbt_matrix_free(bA);
-       bA = xbt_matrix_new_sub(mydataA,
-			       submatrix_size,submatrix_size,
-			       0,0,NULL);
+    if (myrow == step) {
+      VERB2("ROW: step(%d)=myrow(%d). Broadcast my data.", step, myrow);
+      for (l = 1; l < PROC_MATRIX_SIZE; l++) {
+        VERB1("ROW:   Send to %s",
+              gras_socket_peer_name(socket_line[l - 1]));
+        gras_msg_send(socket_line[l - 1], "dataA", &mydataA);
+      }
+      xbt_matrix_free(bA);
+      bA = xbt_matrix_new_sub(mydataA,
+                              submatrix_size, submatrix_size, 0, 0, NULL);
     } else {
       TRY {
-	xbt_matrix_free(bA);
-	gras_msg_wait(1200,gras_msgtype_by_name("dataA"), &from,&bA);
-      } CATCH(e) {
-	RETHROW0("Can't get a data message from row : %s");
+        xbt_matrix_free(bA);
+        gras_msg_wait(1200, "dataA", &from, &bA);
+      }
+      CATCH(e) {
+        RETHROW0("Can't get a data message from row : %s");
       }
-      INFO3("ROW: step(%d)<>myrow(%d). Receive data from %s",step,myrow,
-	    gras_socket_peer_name(from));
+      VERB3("ROW: step(%d)<>myrow(%d). Receive data from %s", step, myrow,
+            gras_socket_peer_name(from));
     }
-    xbt_matrix_double_addmult(bA,bB,bC);
+    xbt_matrix_double_addmult(bA, bB, bC);
 
   };
- 
-  /* send Result to master */  
-  result.C=bC;
-  result.linepos=myline;
-  result.rowpos=myrow;
+
+  /* send Result to master */
+  result.C = bC;
+  result.linepos = myline;
+  result.rowpos = myrow;
 
   TRY {
-    gras_msg_send(master, gras_msgtype_by_name("result"),&result);
-  } CATCH(e) {
+    gras_msg_send(master, "result", &result);
+  }
+  CATCH(e) {
     RETHROW0("Failed to send answer to server: %s");
   }
-  INFO2(">>>>>>>> Result sent to %s:%d <<<<<<<<",
-	gras_socket_peer_name(master),gras_socket_peer_port(master));
+  VERB2(">>>>>>>> Result sent to %s:%d <<<<<<<<",
+        gras_socket_peer_name(master), gras_socket_peer_port(master));
   /*  Free the allocated resources, and shut GRAS down */
 
   xbt_matrix_free(bA);
@@ -349,39 +365,60 @@ static int pmm_worker_cb(gras_msg_cb_ctx_t ctx, void *payload) {
 
   xbt_matrix_free(mydataA);
   xbt_matrix_free(mydataB);
-  gras_socket_close(master);
-  gras_socket_close(from);
   /* FIXME: some are said to be unknown 
-  for (l=0; l < PROC_MATRIX_SIZE-1; l++) {
+     gras_socket_close(master);
+     gras_socket_close(from);
+     for (l=0; l < PROC_MATRIX_SIZE-1; l++) {
      if (socket_line[l])
-       gras_socket_close(socket_line[l]);
+     gras_socket_close(socket_line[l]);
      if (socket_row[l])
-       gras_socket_close(socket_row[l]); 
-  }*/
+     gras_socket_close(socket_row[l]); 
+     } */
 
-  return 1;
+  return 0;
 }
 
-int slave(int argc,char *argv[]) {
+int slave(int argc, char *argv[])
+{
   gras_socket_t mysock;
-  gras_socket_t master;
+  gras_socket_t master = NULL;
+  int connected = 0;
+  int rank;
 
   /* Init the GRAS's infrastructure */
   gras_init(&argc, argv);
   amok_pm_init();
+  if (argc != 3 && argc != 2)
+    xbt_die("Usage: slave masterhost:masterport [rank]");
+  if (argc == 2)
+    rank = -1;
+  else
+    rank = atoi(argv[2]);
 
   /*  Register the known messages and my callback */
   register_messages();
-  gras_cb_register(gras_msgtype_by_name("pmm_slave"),pmm_worker_cb);
+  gras_cb_register("pmm_slave", pmm_worker_cb);
 
   /* Create the connexions */
-  mysock = gras_socket_server_range(3000,9999,0,0);
-  gras_os_sleep(1); /* let the master get ready */
-  INFO1("Sensor starting (on port %d)",gras_os_myport());
-  master = gras_socket_client_from_string(argv[1]);
-				
+  mysock = gras_socket_server_range(3000, 9999, 0, 0);
+  INFO1("Sensor %d starting", rank);
+  while (!connected) {
+    xbt_ex_t e;
+    TRY {
+      master = gras_socket_client_from_string(argv[1]);
+      connected = 1;
+    }
+    CATCH(e) {
+      if (e.category != system_error)
+        RETHROW;
+      xbt_ex_free(e);
+      gras_os_sleep(0.5);
+    }
+  }
+  INFO2("Connected to master: %s:%d",gras_socket_peer_name(master),gras_socket_peer_port(master));
+
   /* Join and run the group */
-  amok_pm_group_join(master,"pmm");
+  rank = amok_pm_group_join(master, "pmm");
   amok_pm_mainloop(600);
 
   /* housekeeping */
@@ -389,4 +426,4 @@ int slave(int argc,char *argv[]) {
   //  gras_socket_close(master); Unknown
   gras_exit();
   return 0;
-} /* end_of_slave */
+}                               /* end_of_slave */