src/surf/network.c

   1 /*      $Id$     */
   2
   3 /* Copyright (c) 2004 Arnaud Legrand. All rights reserved.                  */
   4
   5 /* This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the license (GNU LGPL) which comes with this package. */
   7
   8 #include "network_private.h"
   9 #include "xbt/log.h"
  10 #include "xbt/str.h"
  11
  12 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_network, surf,
  13                                 "Logging specific to the SURF network module");
  14
  15 surf_model_t surf_network_model = NULL;
  16 static lmm_system_t network_maxmin_system = NULL;
  17 static void (*network_solve) (lmm_system_t) = NULL;
  18
  19 double latency_factor = 1.0;    /* default value */
  20 double bandwidth_factor = 1.0;  /* default value */
  21 double weight_S_parameter = 0.0;        /* default value */
  22
  23 int card_number = 0;
  24 int host_count = 0;
  25 double sg_tcp_gamma = 0.0;
  26
  27
  28
  29 static link_CM02_t link_new(char *name,
  30                             double bw_initial,
  31                             tmgr_trace_t bw_trace,
  32                             double lat_initial,
  33                             tmgr_trace_t lat_trace,
  34                             e_surf_link_state_t
  35                             state_initial,
  36                             tmgr_trace_t state_trace,
  37                             e_surf_link_sharing_policy_t
  38                             policy, xbt_dict_t properties)
  39 {
  40   link_CM02_t nw_link = xbt_new0(s_link_CM02_t, 1);
  41   xbt_assert1(!xbt_dict_get_or_null(surf_network_model->resource_set, name),
  42               "Link '%s' declared several times in the platform file.", name);
  43
  44   nw_link->generic_resource.model = surf_network_model;
  45   nw_link->generic_resource.name = name;
  46   current_property_set = nw_link->generic_resource.properties = properties;
  47   nw_link->bw_current = bw_initial;
  48   if (bw_trace)
  49     nw_link->bw_event =
  50       tmgr_history_add_trace(history, bw_trace, 0.0, 0, nw_link);
  51   nw_link->lat_current = lat_initial;
  52   if (lat_trace)
  53     nw_link->lat_event =
  54       tmgr_history_add_trace(history, lat_trace, 0.0, 0, nw_link);
  55   nw_link->state_current = state_initial;
  56   if (state_trace)
  57     nw_link->state_event =
  58       tmgr_history_add_trace(history, state_trace, 0.0, 0, nw_link);
  59
  60   nw_link->constraint =
  61     lmm_constraint_new(network_maxmin_system, nw_link,
  62                        bandwidth_factor * nw_link->bw_current);
  63
  64   if (policy == SURF_LINK_FATPIPE)
  65     lmm_constraint_shared(nw_link->constraint);
  66
  67   xbt_dict_set(surf_network_model->resource_set, name, nw_link, surf_resource_free);
  68
  69   return nw_link;
  70 }
  71
  72 static void parse_link_init(void)
  73 {
  74   char *name_link;
  75   double bw_initial;
  76   tmgr_trace_t bw_trace;
  77   double lat_initial;
  78   tmgr_trace_t lat_trace;
  79   e_surf_link_state_t state_initial_link = SURF_LINK_ON;
  80   e_surf_link_sharing_policy_t policy_initial_link = SURF_LINK_SHARED;
  81   tmgr_trace_t state_trace;
  82
  83   name_link = xbt_strdup(A_surfxml_link_id);
  84   surf_parse_get_double(&bw_initial, A_surfxml_link_bandwidth);
  85   surf_parse_get_trace(&bw_trace, A_surfxml_link_bandwidth_file);
  86   surf_parse_get_double(&lat_initial, A_surfxml_link_latency);
  87   surf_parse_get_trace(&lat_trace, A_surfxml_link_latency_file);
  88
  89   xbt_assert0((A_surfxml_link_state == A_surfxml_link_state_ON)
  90               || (A_surfxml_link_state ==
  91                   A_surfxml_link_state_OFF), "Invalid state");
  92   if (A_surfxml_link_state == A_surfxml_link_state_ON)
  93     state_initial_link = SURF_LINK_ON;
  94   else if (A_surfxml_link_state == A_surfxml_link_state_OFF)
  95     state_initial_link = SURF_LINK_OFF;
  96
  97   if (A_surfxml_link_sharing_policy == A_surfxml_link_sharing_policy_SHARED)
  98     policy_initial_link = SURF_LINK_SHARED;
  99   else if (A_surfxml_link_sharing_policy ==
 100            A_surfxml_link_sharing_policy_FATPIPE)
 101     policy_initial_link = SURF_LINK_FATPIPE;
 102
 103   surf_parse_get_trace(&state_trace, A_surfxml_link_state_file);
 104
 105   link_new(name_link, bw_initial, bw_trace,
 106            lat_initial, lat_trace, state_initial_link, state_trace,
 107            policy_initial_link, xbt_dict_new());
 108
 109 }
 110
 111 static void add_traces(void)
 112 {
 113   xbt_dict_cursor_t cursor = NULL;
 114   char *trace_name, *elm;
 115
 116   static int called = 0;
 117   if (called)
 118     return;
 119   called = 1;
 120
 121   /* connect all traces relative to network */
 122   xbt_dict_foreach(trace_connect_list_link_avail, cursor, trace_name, elm) {
 123     tmgr_trace_t trace = xbt_dict_get_or_null(traces_set_list, trace_name);
 124     link_CM02_t link = xbt_dict_get_or_null(surf_network_model->resource_set, elm);
 125
 126     xbt_assert2(link, "Cannot connect trace %s to link %s: link undefined",
 127                 trace_name, elm);
 128     xbt_assert2(trace, "Cannot connect trace %s to link %s: trace undefined",
 129                 trace_name, elm);
 130
 131     link->state_event = tmgr_history_add_trace(history, trace, 0.0, 0, link);
 132   }
 133
 134   xbt_dict_foreach(trace_connect_list_bandwidth, cursor, trace_name, elm) {
 135     tmgr_trace_t trace = xbt_dict_get_or_null(traces_set_list, trace_name);
 136     link_CM02_t link = xbt_dict_get_or_null(surf_network_model->resource_set, elm);
 137
 138     xbt_assert2(link, "Cannot connect trace %s to link %s: link undefined",
 139                 trace_name, elm);
 140     xbt_assert2(trace, "Cannot connect trace %s to link %s: trace undefined",
 141                 trace_name, elm);
 142
 143     link->bw_event = tmgr_history_add_trace(history, trace, 0.0, 0, link);
 144   }
 145
 146   xbt_dict_foreach(trace_connect_list_latency, cursor, trace_name, elm) {
 147     tmgr_trace_t trace = xbt_dict_get_or_null(traces_set_list, trace_name);
 148     link_CM02_t link = xbt_dict_get_or_null(surf_network_model->resource_set, elm);
 149
 150     xbt_assert2(link, "Cannot connect trace %s to link %s: link undefined",
 151                 trace_name, elm);
 152     xbt_assert2(trace, "Cannot connect trace %s to link %s: trace undefined",
 153                 trace_name, elm);
 154
 155     link->lat_event = tmgr_history_add_trace(history, trace, 0.0, 0, link);
 156   }
 157 }
 158
 159 static void define_callbacks(const char *file)
 160 {
 161   /* Figuring out the network links */
 162   surfxml_add_callback(STag_surfxml_link_cb_list, &parse_link_init);
 163   surfxml_add_callback(ETag_surfxml_platform_cb_list, &add_traces);
 164 }
 165
 166 static int resource_used(void *resource_id)
 167 {
 168   return lmm_constraint_used(network_maxmin_system,
 169                              ((link_CM02_t) resource_id)->constraint);
 170 }
 171
 172 static int action_unref(surf_action_t action)
 173 {
 174   action->refcount--;
 175   if (!action->refcount) {
 176     xbt_swag_remove(action, action->state_set);
 177     if (((surf_action_network_CM02_t) action)->variable)
 178       lmm_variable_free(network_maxmin_system,
 179                         ((surf_action_network_CM02_t) action)->variable);
 180     free(action);
 181     return 1;
 182   }
 183   return 0;
 184 }
 185
 186 static void action_cancel(surf_action_t action)
 187 {
 188   return;
 189 }
 190
 191 static void action_recycle(surf_action_t action)
 192 {
 193   return;
 194 }
 195
 196 static double share_resources(double now)
 197 {
 198   s_surf_action_network_CM02_t s_action;
 199   surf_action_network_CM02_t action = NULL;
 200   xbt_swag_t running_actions = surf_network_model->states.running_action_set;
 201   double min;
 202
 203   min = generic_maxmin_share_resources(running_actions,
 204                                        xbt_swag_offset(s_action,
 205                                                        variable),
 206                                        network_maxmin_system, network_solve);
 207
 208 #define VARIABLE(action) (*((lmm_variable_t*)(((char *) (action)) + xbt_swag_offset(s_action, variable)  )))
 209
 210   xbt_swag_foreach(action, running_actions) {
 211     if (action->latency > 0) {
 212       if (min < 0)
 213         min = action->latency;
 214       else if (action->latency < min)
 215         min = action->latency;
 216     }
 217   }
 218
 219   return min;
 220 }
 221
 222 static void update_actions_state(double now, double delta)
 223 {
 224   double deltap = 0.0;
 225   surf_action_network_CM02_t action = NULL;
 226   surf_action_network_CM02_t next_action = NULL;
 227   xbt_swag_t running_actions = surf_network_model->states.running_action_set;
 228   /*
 229      xbt_swag_t failed_actions =
 230      surf_network_model->states.failed_action_set;
 231    */
 232
 233   xbt_swag_foreach_safe(action, next_action, running_actions) {
 234     deltap = delta;
 235     if (action->latency > 0) {
 236       if (action->latency > deltap) {
 237         double_update(&(action->latency), deltap);
 238         deltap = 0.0;
 239       } else {
 240         double_update(&(deltap), action->latency);
 241         action->latency = 0.0;
 242       }
 243       if ((action->latency == 0.0) && !(action->suspended))
 244         lmm_update_variable_weight(network_maxmin_system, action->variable,
 245                                    action->weight);
 246     }
 247     double_update(&(action->generic_action.remains),
 248                   lmm_variable_getvalue(action->variable) * deltap);
 249     if (action->generic_action.max_duration != NO_MAX_DURATION)
 250       double_update(&(action->generic_action.max_duration), delta);
 251
 252     if ((action->generic_action.remains <= 0) &&
 253         (lmm_get_variable_weight(action->variable) > 0)) {
 254       action->generic_action.finish = surf_get_clock();
 255       surf_network_model->action_state_set((surf_action_t) action, SURF_ACTION_DONE);
 256     } else if ((action->generic_action.max_duration != NO_MAX_DURATION) &&
 257                (action->generic_action.max_duration <= 0)) {
 258       action->generic_action.finish = surf_get_clock();
 259       surf_network_model->action_state_set((surf_action_t) action, SURF_ACTION_DONE);
 260     }
 261   }
 262
 263   return;
 264 }
 265
 266 static void update_resource_state(void *id,
 267                                   tmgr_trace_event_t event_type,
 268                                   double value, double date)
 269 {
 270   link_CM02_t nw_link = id;
 271   /*   printf("[" "%lg" "] Asking to update network card \"%s\" with value " */
 272   /*     "%lg" " for event %p\n", surf_get_clock(), nw_link->name, */
 273   /*     value, event_type); */
 274
 275   if (event_type == nw_link->bw_event) {
 276     double delta =
 277       weight_S_parameter / value - weight_S_parameter / nw_link->bw_current;
 278     lmm_variable_t var = NULL;
 279     lmm_element_t elem = NULL;
 280     surf_action_network_CM02_t action = NULL;
 281
 282     nw_link->bw_current = value;
 283     lmm_update_constraint_bound(network_maxmin_system, nw_link->constraint,
 284                                 bandwidth_factor * nw_link->bw_current);
 285     if (weight_S_parameter > 0) {
 286       while ((var = lmm_get_var_from_cnst
 287               (network_maxmin_system, nw_link->constraint, &elem))) {
 288         action = lmm_variable_id(var);
 289         action->weight += delta;
 290         if (!(action->suspended))
 291           lmm_update_variable_weight(network_maxmin_system, action->variable,
 292                                      action->weight);
 293       }
 294     }
 295   } else if (event_type == nw_link->lat_event) {
 296     double delta = value - nw_link->lat_current;
 297     lmm_variable_t var = NULL;
 298     lmm_element_t elem = NULL;
 299     surf_action_network_CM02_t action = NULL;
 300
 301     nw_link->lat_current = value;
 302     while ((var = lmm_get_var_from_cnst
 303             (network_maxmin_system, nw_link->constraint, &elem))) {
 304       action = lmm_variable_id(var);
 305       action->lat_current += delta;
 306       action->weight += delta;
 307       if (action->rate < 0)
 308         lmm_update_variable_bound(network_maxmin_system, action->variable,
 309                                   sg_tcp_gamma / (2.0 * action->lat_current));
 310       else
 311         lmm_update_variable_bound(network_maxmin_system, action->variable,
 312                                   min(action->rate,
 313                                       sg_tcp_gamma / (2.0 *
 314                                                       action->lat_current)));
 315       if (!(action->suspended))
 316         lmm_update_variable_weight(network_maxmin_system, action->variable,
 317                                    action->weight);
 318
 319     }
 320   } else if (event_type == nw_link->state_event) {
 321     if (value > 0)
 322       nw_link->state_current = SURF_LINK_ON;
 323     else {
 324       lmm_constraint_t cnst = nw_link->constraint;
 325       lmm_variable_t var = NULL;
 326       lmm_element_t elem = NULL;
 327
 328       nw_link->state_current = SURF_LINK_OFF;
 329       while ((var = lmm_get_var_from_cnst
 330               (network_maxmin_system, cnst, &elem))) {
 331         surf_action_t action = lmm_variable_id(var);
 332
 333         if (surf_action_state_get(action) == SURF_ACTION_RUNNING ||
 334             surf_action_state_get(action) == SURF_ACTION_READY) {
 335           action->finish = date;
 336           surf_network_model->action_state_set(action, SURF_ACTION_FAILED);
 337         }
 338       }
 339     }
 340   } else {
 341     CRITICAL0("Unknown event ! \n");
 342     xbt_abort();
 343   }
 344
 345   return;
 346 }
 347
 348 static surf_action_t communicate(const char *src_name, const char *dst_name,int src, int dst, double size,
 349                                  double rate)
 350 {
 351   surf_action_network_CM02_t action = NULL;
 352   /* LARGE PLATFORMS HACK:
 353      Add a link_CM02_t *link and a int link_nb to network_card_CM02_t. It will represent local links for this node
 354      Use the cluster_id for ->id */
 355   xbt_dynar_t route = used_routing->get_route(src, dst);
 356   /* LARGE PLATFORMS HACK:
 357      total_route_size = route_size + src->link_nb + dst->nb */
 358   unsigned int i;
 359
 360   XBT_IN4("(%s,%s,%g,%g)", src_name, dst_name, size, rate);
 361   /* LARGE PLATFORMS HACK:
 362      assert on total_route_size */
 363   xbt_assert2(xbt_dynar_length(route),
 364               "You're trying to send data from %s to %s but there is no connection between these two hosts.",
 365               src_name, dst_name);
 366
 367   link_CM02_t link;
 368   int failed=0;
 369   xbt_dynar_foreach(route,i,link) {
 370     if (link->state_current == SURF_LINK_OFF) {
 371       failed = 1;
 372       break;
 373     }
 374   }
 375   action = surf_action_new(sizeof(s_surf_action_network_CM02_t),size,surf_network_model,failed);
 376
 377   xbt_swag_insert(action, action->generic_action.state_set);
 378   action->rate = rate;
 379
 380   action->latency = 0.0;
 381   action->weight = 0.0;
 382   xbt_dynar_foreach(route,i,link) {
 383     action->latency += link->lat_current;
 384     action->weight +=
 385       link->lat_current + weight_S_parameter / link->bw_current;
 386   }
 387   /* LARGE PLATFORMS HACK:
 388      Add src->link and dst->link latencies */
 389   action->lat_current = action->latency;
 390   action->latency *= latency_factor;
 391
 392   /* LARGE PLATFORMS HACK:
 393      lmm_variable_new(..., total_route_size) */
 394   if (action->latency > 0)
 395     action->variable =
 396       lmm_variable_new(network_maxmin_system, action, 0.0, -1.0, xbt_dynar_length(route));
 397   else
 398     action->variable =
 399       lmm_variable_new(network_maxmin_system, action, 1.0, -1.0, xbt_dynar_length(route));
 400
 401   if (action->rate < 0) {
 402     if (action->lat_current > 0)
 403       lmm_update_variable_bound(network_maxmin_system, action->variable,
 404                                 sg_tcp_gamma / (2.0 * action->lat_current));
 405     else
 406       lmm_update_variable_bound(network_maxmin_system, action->variable,
 407                                 -1.0);
 408   } else {
 409     if (action->lat_current > 0)
 410       lmm_update_variable_bound(network_maxmin_system, action->variable,
 411                                 min(action->rate,
 412                                     sg_tcp_gamma / (2.0 *
 413                                                     action->lat_current)));
 414     else
 415       lmm_update_variable_bound(network_maxmin_system, action->variable,
 416                                 action->rate);
 417   }
 418
 419   xbt_dynar_foreach(route,i,link) {
 420     lmm_expand(network_maxmin_system, link->constraint,
 421                action->variable, 1.0);
 422   }
 423   /* LARGE PLATFORMS HACK:
 424      expand also with src->link and dst->link */
 425
 426   XBT_OUT;
 427
 428   return (surf_action_t) action;
 429 }
 430
 431 static double get_link_bandwidth(const void *link)
 432 {
 433   return ((link_CM02_t) link)->bw_current;
 434 }
 435
 436 static double get_link_latency(const void *link)
 437 {
 438   return ((link_CM02_t) link)->lat_current;
 439 }
 440
 441 static int link_shared(const void *link)
 442 {
 443   return lmm_constraint_is_shared(((link_CM02_t) link)->constraint);
 444 }
 445
 446 static void action_suspend(surf_action_t action)
 447 {
 448   ((surf_action_network_CM02_t) action)->suspended = 1;
 449   lmm_update_variable_weight(network_maxmin_system,
 450                              ((surf_action_network_CM02_t) action)->variable,
 451                              0.0);
 452 }
 453
 454 static void action_resume(surf_action_t action)
 455 {
 456   if (((surf_action_network_CM02_t) action)->suspended) {
 457     lmm_update_variable_weight(network_maxmin_system,
 458                                ((surf_action_network_CM02_t)
 459                                 action)->variable,
 460                                ((surf_action_network_CM02_t) action)->weight);
 461     ((surf_action_network_CM02_t) action)->suspended = 0;
 462   }
 463 }
 464
 465 static int action_is_suspended(surf_action_t action)
 466 {
 467   return ((surf_action_network_CM02_t) action)->suspended;
 468 }
 469
 470 static void action_set_max_duration(surf_action_t action, double duration)
 471 {
 472   action->max_duration = duration;
 473 }
 474
 475 static void finalize(void)
 476 {
 477   surf_model_exit(surf_network_model);
 478   surf_network_model = NULL;
 479
 480   used_routing->finalize();
 481   host_count = 0;
 482   lmm_system_free(network_maxmin_system);
 483   network_maxmin_system = NULL;
 484 }
 485
 486 static void surf_network_model_init_internal(void)
 487 {
 488   surf_network_model = surf_model_init();
 489
 490   surf_network_model->name = "network";
 491   surf_network_model->action_unref = action_unref;
 492   surf_network_model->action_cancel = action_cancel;
 493   surf_network_model->action_recycle = action_recycle;
 494
 495   surf_network_model->model_private->resource_used = resource_used;
 496   surf_network_model->model_private->share_resources = share_resources;
 497   surf_network_model->model_private->update_actions_state =
 498     update_actions_state;
 499   surf_network_model->model_private->update_resource_state =
 500     update_resource_state;
 501   surf_network_model->model_private->finalize = finalize;
 502
 503   surf_network_model->suspend = action_suspend;
 504   surf_network_model->resume = action_resume;
 505   surf_network_model->is_suspended = action_is_suspended;
 506   surf_cpu_model->set_max_duration = action_set_max_duration;
 507
 508   surf_network_model->extension.network.communicate = communicate;
 509   surf_network_model->extension.network.get_link_bandwidth =
 510     get_link_bandwidth;
 511   surf_network_model->extension.network.get_link_latency = get_link_latency;
 512   surf_network_model->extension.network.link_shared = link_shared;
 513
 514   if (!network_maxmin_system)
 515     network_maxmin_system = lmm_system_new();
 516
 517   routing_model_full_create(sizeof(link_CM02_t),
 518       link_new(xbt_strdup("__loopback__"),
 519           498000000, NULL, 0.000015, NULL,
 520           SURF_LINK_ON, NULL, SURF_LINK_FATPIPE, NULL));
 521 }
 522
 523 /************************************************************************/
 524 /* New model based on optimizations discussed during this thesis        */
 525 /************************************************************************/
 526 void surf_network_model_init_LegrandVelho(const char *filename)
 527 {
 528
 529   if (surf_network_model)
 530     return;
 531   surf_network_model_init_internal();
 532   define_callbacks(filename);
 533   xbt_dynar_push(model_list, &surf_network_model);
 534   network_solve = lmm_solve;
 535
 536   latency_factor = 10.4;
 537   bandwidth_factor = 0.92;
 538   weight_S_parameter = 8775;
 539
 540   update_model_description(surf_network_model_description,
 541                            "LegrandVelho", surf_network_model);
 542 }
 543
 544 /***************************************************************************/
 545 /* The nice TCP sharing model designed by Loris Marchal and Henri Casanova */
 546 /***************************************************************************/
 547 /* @TechReport{      rr-lip2002-40, */
 548 /*   author        = {Henri Casanova and Loris Marchal}, */
 549 /*   institution   = {LIP}, */
 550 /*   title         = {A Network Model for Simulation of Grid Application}, */
 551 /*   number        = {2002-40}, */
 552 /*   month         = {oct}, */
 553 /*   year          = {2002} */
 554 /* } */
 555 void surf_network_model_init_CM02(const char *filename)
 556 {
 557
 558   if (surf_network_model)
 559     return;
 560   surf_network_model_init_internal();
 561   define_callbacks(filename);
 562   xbt_dynar_push(model_list, &surf_network_model);
 563   network_solve = lmm_solve;
 564
 565   update_model_description(surf_network_model_description,
 566                            "CM02", surf_network_model);
 567 }
 568
 569 void surf_network_model_init_Reno(const char *filename)
 570 {
 571   if (surf_network_model)
 572     return;
 573   surf_network_model_init_internal();
 574   define_callbacks(filename);
 575
 576   xbt_dynar_push(model_list, &surf_network_model);
 577   lmm_set_default_protocol_function(func_reno_f, func_reno_fp, func_reno_fpi);
 578   network_solve = lagrange_solve;
 579
 580   latency_factor = 10.4;
 581   bandwidth_factor = 0.92;
 582   weight_S_parameter = 8775;
 583
 584   update_model_description(surf_network_model_description,
 585                            "Reno", surf_network_model);
 586 }
 587
 588
 589 void surf_network_model_init_Reno2(const char *filename)
 590 {
 591   if (surf_network_model)
 592     return;
 593   surf_network_model_init_internal();
 594   define_callbacks(filename);
 595
 596   xbt_dynar_push(model_list, &surf_network_model);
 597   lmm_set_default_protocol_function(func_reno2_f, func_reno2_fp,
 598                                     func_reno2_fpi);
 599   network_solve = lagrange_solve;
 600
 601   latency_factor = 10.4;
 602   bandwidth_factor = 0.92;
 603   weight_S_parameter = 8775;
 604
 605   update_model_description(surf_network_model_description,
 606                            "Reno2", surf_network_model);
 607 }
 608
 609 void surf_network_model_init_Vegas(const char *filename)
 610 {
 611   if (surf_network_model)
 612     return;
 613   surf_network_model_init_internal();
 614   define_callbacks(filename);
 615
 616   xbt_dynar_push(model_list, &surf_network_model);
 617   lmm_set_default_protocol_function(func_vegas_f, func_vegas_fp,
 618                                     func_vegas_fpi);
 619   network_solve = lagrange_solve;
 620
 621   latency_factor = 10.4;
 622   bandwidth_factor = 0.92;
 623   weight_S_parameter = 8775;
 624
 625   update_model_description(surf_network_model_description,
 626                            "Vegas", surf_network_model);
 627 }
 628
 629 #ifdef HAVE_SDP
 630 void surf_network_model_init_SDP(const char *filename)
 631 {
 632   if (surf_network_model)
 633     return;
 634   surf_network_model_init_internal();
 635   define_callbacks(filename);
 636
 637   xbt_dynar_push(model_list, &surf_network_model);
 638   network_solve = sdp_solve;
 639
 640   update_model_description(surf_network_model_description,
 641                            "SDP", surf_network_model);
 642 }
 643 #endif