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Enable generic_lmm_action to be lazily updated by refactoring the corresponding fields:
[simgrid.git] / src / surf / network.c
index 6e6e794..493623e 100644 (file)
@@ -1,4 +1,12 @@
-/* Copyright (c) 2004, 2005, 2006, 2007, 2008, 2009, 2010. The SimGrid Team.
+
+/*
+ * Network with improved management of tasks, IM (Improved Management).
+ * Uses a heap to store actions so that the share_resources is faster.
+ * This model automatically sets the selective update flag to 1 and is
+ * highly dependent on the maxmin lmm module.
+ */
+
+/* Copyright (c) 2009, 2010, 2011. The SimGrid Team.
  * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
@@ -8,6 +16,19 @@
 #include "xbt/log.h"
 #include "xbt/str.h"
 
+#include "surf_private.h"
+#include "xbt/dict.h"
+#include "maxmin_private.h"
+#include "surf/surfxml_parse_values.h"
+#include "surf/surf_resource.h"
+#include "surf/surf_resource_lmm.h"
+
+#undef GENERIC_LMM_ACTION
+#undef GENERIC_ACTION
+#define GENERIC_LMM_ACTION(action) (action)->generic_lmm_action
+#define GENERIC_ACTION(action) GENERIC_LMM_ACTION(action).generic_action
+
+
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_network, surf,
                                 "Logging specific to the SURF network module");
 
@@ -15,73 +36,61 @@ surf_model_t surf_network_model = NULL;
 static lmm_system_t network_maxmin_system = NULL;
 static void (*network_solve) (lmm_system_t) = NULL;
 
+xbt_dynar_t smpi_bw_factor = NULL;
+xbt_dynar_t smpi_lat_factor = NULL;
+
+typedef struct s_smpi_factor *smpi_factor_t;
+typedef struct s_smpi_factor {
+  long factor;
+  double value;
+} s_smpi_factor_t;
+
 double sg_sender_gap = 0.0;
 double sg_latency_factor = 1.0; /* default value; can be set by model or from command line */
 double sg_bandwidth_factor = 1.0;       /* default value; can be set by model or from command line */
 double sg_weight_S_parameter = 0.0;     /* default value; can be set by model or from command line */
 
 double sg_tcp_gamma = 0.0;
-int sg_network_fullduplex = 0;
+int sg_network_crosstraffic = 0;
 
 xbt_dict_t gap_lookup = NULL;
 
-static double net_get_link_bandwidth(const void *link);
+e_UM_t network_update_mechanism = UM_UNDEFINED;
+static int net_selective_update = 0;
 
-static void gap_append(double size, const link_CM02_t link, surf_action_network_CM02_t action) {
-   const char* src = link->lmm_resource.generic_resource.name;
-   xbt_fifo_t fifo;
-   surf_action_network_CM02_t last_action;
-   double bw;
+static int net_action_is_suspended(surf_action_t action);
+static void update_action_remaining_lazy(double now);
 
-   if(sg_sender_gap > 0.0) {
-      if(!gap_lookup) {
-         gap_lookup = xbt_dict_new();
-      }
-      fifo = (xbt_fifo_t)xbt_dict_get_or_null(gap_lookup, src);
-      action->sender.gap = 0.0;
-      if(fifo && xbt_fifo_size(fifo) > 0) {
-         /* Compute gap from last send */
-         last_action = (surf_action_network_CM02_t)xbt_fifo_get_item_content(xbt_fifo_get_last_item(fifo));
-         bw = net_get_link_bandwidth(link);
-         action->sender.gap = last_action->sender.gap + max(sg_sender_gap, last_action->sender.size / bw);
-         action->latency += action->sender.gap;
-      }
-      /* Append action as last send */
-      action->sender.link_name = link->lmm_resource.generic_resource.name;
-      fifo = (xbt_fifo_t)xbt_dict_get_or_null(gap_lookup, action->sender.link_name);
-      if(!fifo) {
-         fifo = xbt_fifo_new();
-         xbt_dict_set(gap_lookup, action->sender.link_name, fifo, NULL);
-      }
-      action->sender.fifo_item = xbt_fifo_push(fifo, action);
-      action->sender.size = size;
-   }
-}
-
-static void gap_unknown(surf_action_network_CM02_t action) {
-   action->sender.gap = 0.0;
-   action->sender.link_name = NULL;
-   action->sender.fifo_item = NULL;
-   action->sender.size = 0.0;
-}
-
-static void gap_remove(surf_action_network_CM02_t action) {
-   xbt_fifo_t fifo;
-   size_t size;
-
-   if(sg_sender_gap > 0.0 && action->sender.link_name && action->sender.fifo_item) {
-      fifo = (xbt_fifo_t)xbt_dict_get_or_null(gap_lookup, action->sender.link_name);
-      xbt_fifo_remove_item(fifo, action->sender.fifo_item);
-      size = xbt_fifo_size(fifo);
-      if(size == 0) {
-         xbt_fifo_free(fifo);
-         xbt_dict_remove(gap_lookup, action->sender.link_name);
-         size = xbt_dict_size(gap_lookup);
-         if(size == 0) {
-            xbt_dict_free(&gap_lookup);
-         }
-      }
-   }
+static xbt_swag_t net_modified_set = NULL;
+static xbt_heap_t net_action_heap = NULL;
+
+/* added to manage the communication action's heap */
+static void net_action_update_index_heap(void *action, int i)
+{
+  surf_action_network_CM02_t a = action;
+  GENERIC_LMM_ACTION(a).index_heap = i;
+}
+
+/* insert action on heap using a given key and a hat (heap_action_type)
+ * a hat can be of three types for communications:
+ *
+ * NORMAL = this is a normal heap entry stating the date to finish transmitting
+ * LATENCY = this is a heap entry to warn us when the latency is payed
+ * MAX_DURATION =this is a heap entry to warn us when the max_duration limit is reached
+ */
+static void heap_insert(surf_action_network_CM02_t action, double key,
+                        enum heap_action_type hat)
+{
+  GENERIC_LMM_ACTION(action).hat = hat;
+  xbt_heap_push(net_action_heap, action, key);
+}
+
+static void heap_remove(surf_action_network_CM02_t action)
+{
+  GENERIC_LMM_ACTION(action).hat = NOTSET;
+  if (GENERIC_LMM_ACTION(action).index_heap >= 0) {
+    xbt_heap_remove(net_action_heap, GENERIC_LMM_ACTION(action).index_heap);
+  }
 }
 
 /******************************************************************************/
@@ -103,53 +112,69 @@ static double constant_bandwidth_constraint(double rate, double bound,
   return rate;
 }
 
-/**--------- <copy/paste C code snippet in surf/network.c> -------------
-  * produced by:
-  * ./regression2.py ./pingpong-in.dat 0.15 100 2 2.4e-5 1.25e8
-  * outliers: 65
-  * gnuplot: 
-    plot "./pingpong-in.dat" using 1:2 with lines title "data", \
-        (x >= 65472) ? 0.00850436*x+558.894 : \
-        (x >= 15424) ? 0.0114635*x+167.446 : \
-        (x >= 9376) ? 0.0136219*x+124.464 : \
-        (x >= 5776) ? 0.00735707*x+105.022 : \
-        (x >= 3484) ? 0.0103235*x+90.2886 : \
-        (x >= 1426) ? 0.0131384*x+77.3159 : \
-        (x >= 732) ? 0.0233927*x+93.6146 : \
-        (x >= 257) ? 0.0236608*x+93.7637 : \
-        (x >= 0) ? 0.00985119*x+96.704 : \
-        1.0 with lines title "piecewise function"
-  *-------------------------------------------------------------------*/
+/**********************/
+/*   SMPI callbacks   */
+/**********************/
+static xbt_dynar_t parse_factor(const char *smpi_coef_string)
+{
+  char *value = NULL;
+  unsigned int iter = 0;
+  s_smpi_factor_t fact;
+  xbt_dynar_t smpi_factor, radical_elements, radical_elements2 = NULL;
+
+  smpi_factor = xbt_dynar_new(sizeof(s_smpi_factor_t), NULL);
+  radical_elements = xbt_str_split(smpi_coef_string, ";");
+  xbt_dynar_foreach(radical_elements, iter, value) {
+
+    radical_elements2 = xbt_str_split(value, ":");
+    if (xbt_dynar_length(radical_elements2) != 2)
+      xbt_die("Malformed radical for smpi factor!");
+    fact.factor = atol(xbt_dynar_get_as(radical_elements2, 0, char *));
+    fact.value = atof(xbt_dynar_get_as(radical_elements2, 1, char *));
+    xbt_dynar_push_as(smpi_factor, s_smpi_factor_t, fact);
+    XBT_DEBUG("smpi_factor:\t%ld : %f", fact.factor, fact.value);
+    xbt_dynar_free(&radical_elements2);
+  }
+  xbt_dynar_free(&radical_elements);
+  return smpi_factor;
+}
 
 static double smpi_bandwidth_factor(double size)
 {
+  if (!smpi_bw_factor)
+    smpi_bw_factor =
+        parse_factor(xbt_cfg_get_string(_surf_cfg_set, "smpi/bw_factor"));
+
+  unsigned int iter = 0;
+  s_smpi_factor_t fact;
+  xbt_dynar_foreach(smpi_bw_factor, iter, fact) {
+    if (size >= fact.factor) {
+      XBT_DEBUG("%lf >= %ld return %f", size, fact.factor, fact.value);
+      return fact.value;
+    }
+  }
 
-    if (size >= 65472) return 0.940694;
-    if (size >= 15424) return 0.697866;
-    if (size >= 9376) return 0.58729;
-    if (size >= 5776) return 1.08739;
-    if (size >= 3484) return 0.77493;
-    if (size >= 1426) return 0.608902;
-    if (size >= 732) return 0.341987;
-    if (size >= 257) return 0.338112;
-    if (size >= 0) return 0.812084;
-    return 1.0;
+  return 1.0;
 }
 
 static double smpi_latency_factor(double size)
 {
+  if (!smpi_lat_factor)
+    smpi_lat_factor =
+        parse_factor(xbt_cfg_get_string(_surf_cfg_set, "smpi/lat_factor"));
+
+  unsigned int iter = 0;
+  s_smpi_factor_t fact;
+  xbt_dynar_foreach(smpi_lat_factor, iter, fact) {
+    if (size >= fact.factor) {
+      XBT_DEBUG("%lf >= %ld return %f", size, fact.factor, fact.value);
+      return fact.value;
+    }
+  }
 
-    if (size >= 65472) return 11.6436;
-    if (size >= 15424) return 3.48845;
-    if (size >= 9376) return 2.59299;
-    if (size >= 5776) return 2.18796;
-    if (size >= 3484) return 1.88101;
-    if (size >= 1426) return 1.61075;
-    if (size >= 732) return 1.9503;
-    if (size >= 257) return 1.95341;
-    if (size >= 0) return 2.01467;
-    return 1.0;
+  return 1.0;
 }
+
 /**--------- <copy/paste C code snippet in surf/network.c> -----------*/
 
 static double smpi_bandwidth_constraint(double rate, double bound,
@@ -158,7 +183,6 @@ static double smpi_bandwidth_constraint(double rate, double bound,
   return rate < 0 ? bound : min(bound, rate * smpi_bandwidth_factor(size));
 }
 
-
 static double (*latency_factor_callback) (double) =
     &constant_latency_factor;
 static double (*bandwidth_factor_callback) (double) =
@@ -166,17 +190,20 @@ static double (*bandwidth_factor_callback) (double) =
 static double (*bandwidth_constraint_callback) (double, double, double) =
     &constant_bandwidth_constraint;
 
-
-static link_CM02_t net_link_new(char *name,
-                                double bw_initial,
-                                tmgr_trace_t bw_trace,
-                                double lat_initial,
-                                tmgr_trace_t lat_trace,
-                                e_surf_resource_state_t
-                                state_initial,
-                                tmgr_trace_t state_trace,
-                                e_surf_link_sharing_policy_t
-                                policy, xbt_dict_t properties)
+static void (*gap_append) (double, const link_CM02_t,
+                           surf_action_network_CM02_t) = NULL;
+static void (*gap_remove) (surf_action_network_CM02_t) = NULL;
+
+static void *net_create_resource(const char *name,
+                                 double bw_initial,
+                                 tmgr_trace_t bw_trace,
+                                 double lat_initial,
+                                 tmgr_trace_t lat_trace,
+                                 e_surf_resource_state_t
+                                 state_initial,
+                                 tmgr_trace_t state_trace,
+                                 e_surf_link_sharing_policy_t
+                                 policy, xbt_dict_t properties)
 {
   link_CM02_t nw_link = (link_CM02_t)
       surf_resource_lmm_new(sizeof(s_link_CM02_t),
@@ -188,8 +215,8 @@ static link_CM02_t net_link_new(char *name,
                             bw_initial, bw_trace);
 
   xbt_assert(!xbt_lib_get_or_null(link_lib, name, SURF_LINK_LEVEL),
-              "Link '%s' declared several times in the platform file.",
-              name);
+             "Link '%s' declared several times in the platform file.",
+             name);
 
   nw_link->lat_current = lat_initial;
   if (lat_trace)
@@ -204,75 +231,37 @@ static link_CM02_t net_link_new(char *name,
   return nw_link;
 }
 
-static void net_parse_link_init(void)
-{
-  char *name_link;
-  double bw_initial;
-  tmgr_trace_t bw_trace;
-  double lat_initial;
-  tmgr_trace_t lat_trace;
-  e_surf_resource_state_t state_initial_link = SURF_RESOURCE_ON;
-  e_surf_link_sharing_policy_t policy_initial_link = SURF_LINK_SHARED;
-  tmgr_trace_t state_trace;
-  XBT_DEBUG("link_CM02");
-  name_link = xbt_strdup(A_surfxml_link_id);
-  surf_parse_get_double(&bw_initial, A_surfxml_link_bandwidth);
-  bw_trace = tmgr_trace_new(A_surfxml_link_bandwidth_file);
-  surf_parse_get_double(&lat_initial, A_surfxml_link_latency);
-  lat_trace = tmgr_trace_new(A_surfxml_link_latency_file);
-
-  xbt_assert((A_surfxml_link_state == A_surfxml_link_state_ON)
-              || (A_surfxml_link_state ==
-                  A_surfxml_link_state_OFF), "Invalid state");
-  if (A_surfxml_link_state == A_surfxml_link_state_ON)
-    state_initial_link = SURF_RESOURCE_ON;
-  else if (A_surfxml_link_state == A_surfxml_link_state_OFF)
-    state_initial_link = SURF_RESOURCE_OFF;
-
-  if (A_surfxml_link_sharing_policy == A_surfxml_link_sharing_policy_SHARED)
-    policy_initial_link = SURF_LINK_SHARED;
-  else
-         {
-         if (A_surfxml_link_sharing_policy == A_surfxml_link_sharing_policy_FATPIPE)
-                 policy_initial_link = SURF_LINK_FATPIPE;
-         else if (A_surfxml_link_sharing_policy == A_surfxml_link_sharing_policy_FULLDUPLEX)
-                 policy_initial_link = SURF_LINK_FULLDUPLEX;
-         }
-
-  state_trace = tmgr_trace_new(A_surfxml_link_state_file);
-
-  if(policy_initial_link == SURF_LINK_FULLDUPLEX)
-  {
-         net_link_new(bprintf("%s_UP",name_link), bw_initial, bw_trace,
-                      lat_initial, lat_trace, state_initial_link, state_trace,
-                      policy_initial_link, xbt_dict_new());
-         net_link_new(bprintf("%s_DOWN",name_link), bw_initial, bw_trace,
-                      lat_initial, lat_trace, state_initial_link, state_trace,
-                      policy_initial_link, xbt_dict_new());
-  }
-  else
-  {
-         net_link_new(name_link, bw_initial, bw_trace,
-                      lat_initial, lat_trace, state_initial_link, state_trace,
-                      policy_initial_link, xbt_dict_new());
-  }
-
-}
-
-static void net_create_resource(char *name,
-                                double bw_initial,
-                                tmgr_trace_t bw_trace,
-                                double lat_initial,
-                                tmgr_trace_t lat_trace,
-                                e_surf_resource_state_t
-                                state_initial,
-                                tmgr_trace_t state_trace,
-                                e_surf_link_sharing_policy_t policy,
-                                xbt_dict_t properties)
+static void net_parse_link_init(sg_platf_link_cbarg_t link)
 {
-  net_link_new(name, bw_initial, bw_trace,
-               lat_initial, lat_trace, state_initial, state_trace,
-               policy, xbt_dict_new());
+  if (link->policy == SURF_LINK_FULLDUPLEX) {
+    char *link_id;
+    link_id = bprintf("%s_UP", link->id);
+    net_create_resource(link_id,
+                        link->bandwidth,
+                        link->bandwidth_trace,
+                        link->latency,
+                        link->latency_trace,
+                        link->state,
+                        link->state_trace, link->policy, link->properties);
+    xbt_free(link_id);
+    link_id = bprintf("%s_DOWN", link->id);
+    net_create_resource(link_id,
+                        link->bandwidth,
+                        link->bandwidth_trace,
+                        link->latency,
+                        link->latency_trace,
+                        link->state,
+                        link->state_trace, link->policy, link->properties);
+    xbt_free(link_id);
+  } else {
+    net_create_resource(link->id,
+                        link->bandwidth,
+                        link->bandwidth_trace,
+                        link->latency,
+                        link->latency_trace,
+                        link->state,
+                        link->state_trace, link->policy, link->properties);
+  }
 }
 
 static void net_add_traces(void)
@@ -288,14 +277,13 @@ static void net_add_traces(void)
   /* connect all traces relative to network */
   xbt_dict_foreach(trace_connect_list_link_avail, cursor, trace_name, elm) {
     tmgr_trace_t trace = xbt_dict_get_or_null(traces_set_list, trace_name);
-    link_CM02_t link =
-        xbt_lib_get_or_null(link_lib, elm, SURF_LINK_LEVEL);
+    link_CM02_t link = xbt_lib_get_or_null(link_lib, elm, SURF_LINK_LEVEL);
 
     xbt_assert(link, "Cannot connect trace %s to link %s: link undefined",
-                trace_name, elm);
+               trace_name, elm);
     xbt_assert(trace,
-                "Cannot connect trace %s to link %s: trace undefined",
-                trace_name, elm);
+               "Cannot connect trace %s to link %s: trace undefined",
+               trace_name, elm);
 
     link->lmm_resource.state_event =
         tmgr_history_add_trace(history, trace, 0.0, 0, link);
@@ -303,14 +291,13 @@ static void net_add_traces(void)
 
   xbt_dict_foreach(trace_connect_list_bandwidth, cursor, trace_name, elm) {
     tmgr_trace_t trace = xbt_dict_get_or_null(traces_set_list, trace_name);
-    link_CM02_t link =
-               xbt_lib_get_or_null(link_lib, elm, SURF_LINK_LEVEL);
+    link_CM02_t link = xbt_lib_get_or_null(link_lib, elm, SURF_LINK_LEVEL);
 
     xbt_assert(link, "Cannot connect trace %s to link %s: link undefined",
-                trace_name, elm);
+               trace_name, elm);
     xbt_assert(trace,
-                "Cannot connect trace %s to link %s: trace undefined",
-                trace_name, elm);
+               "Cannot connect trace %s to link %s: trace undefined",
+               trace_name, elm);
 
     link->lmm_resource.power.event =
         tmgr_history_add_trace(history, trace, 0.0, 0, link);
@@ -318,31 +305,30 @@ static void net_add_traces(void)
 
   xbt_dict_foreach(trace_connect_list_latency, cursor, trace_name, elm) {
     tmgr_trace_t trace = xbt_dict_get_or_null(traces_set_list, trace_name);
-    link_CM02_t link =
-               xbt_lib_get_or_null(link_lib, elm, SURF_LINK_LEVEL);
+    link_CM02_t link = xbt_lib_get_or_null(link_lib, elm, SURF_LINK_LEVEL);
 
     xbt_assert(link, "Cannot connect trace %s to link %s: link undefined",
-                trace_name, elm);
+               trace_name, elm);
     xbt_assert(trace,
-                "Cannot connect trace %s to link %s: trace undefined",
-                trace_name, elm);
+               "Cannot connect trace %s to link %s: trace undefined",
+               trace_name, elm);
 
     link->lat_event = tmgr_history_add_trace(history, trace, 0.0, 0, link);
   }
 }
 
-static void net_define_callbacks(const char *file)
+static void net_define_callbacks(void)
 {
   /* Figuring out the network links */
-  surfxml_add_callback(STag_surfxml_link_cb_list, &net_parse_link_init);
-  surfxml_add_callback(ETag_surfxml_platform_cb_list, &net_add_traces);
+  sg_platf_link_add_cb(net_parse_link_init);
+  sg_platf_postparse_add_cb(net_add_traces);
 }
 
 static int net_resource_used(void *resource_id)
 {
-  return lmm_constraint_used(network_maxmin_system,
-                             ((surf_resource_lmm_t)
-                              resource_id)->constraint);
+  return lmm_constraint_used(network_maxmin_system, ((surf_resource_lmm_t)
+                                                     resource_id)->
+                             constraint);
 }
 
 static int net_action_unref(surf_action_t action)
@@ -350,14 +336,18 @@ static int net_action_unref(surf_action_t action)
   action->refcount--;
   if (!action->refcount) {
     xbt_swag_remove(action, action->state_set);
-    if (((surf_action_network_CM02_t) action)->variable)
+    if (((surf_action_lmm_t)action)->variable) {
       lmm_variable_free(network_maxmin_system,
-                        ((surf_action_network_CM02_t) action)->variable);
+                        ((surf_action_lmm_t) action)->variable);
+    }
+    if (network_update_mechanism == UM_LAZY) {  // remove action from the heap
+      heap_remove((surf_action_network_CM02_t) action);
+      xbt_swag_remove(action, net_modified_set);
+    }
 #ifdef HAVE_TRACING
     xbt_free(((surf_action_network_CM02_t) action)->src_name);
     xbt_free(((surf_action_network_CM02_t) action)->dst_name);
-    if (action->category)
-      xbt_free(action->category);
+    xbt_free(action->category);
 #endif
     surf_action_free(&action);
     return 1;
@@ -365,9 +355,16 @@ static int net_action_unref(surf_action_t action)
   return 0;
 }
 
+
+
 static void net_action_cancel(surf_action_t action)
 {
+  XBT_DEBUG("cancel action %p", action);
   surf_network_model->action_state_set(action, SURF_ACTION_FAILED);
+  if (network_update_mechanism == UM_LAZY) {    // remove action from the heap
+    xbt_swag_remove(action, net_modified_set);
+    heap_remove((surf_action_network_CM02_t) action);
+  }
 }
 
 void net_action_recycle(surf_action_t action)
@@ -384,12 +381,51 @@ int net_get_link_latency_limited(surf_action_t action)
 
 double net_action_get_remains(surf_action_t action)
 {
+  if (network_update_mechanism == UM_LAZY)      /* update remains before return it */
+    update_action_remaining_lazy(surf_get_clock());
   return action->remains;
 }
 
-static double net_share_resources(double now)
+static void update_action_remaining_lazy(double now)
 {
-  s_surf_action_network_CM02_t s_action;
+  surf_action_network_CM02_t action = NULL;
+  double delta = 0.0;
+
+  xbt_swag_foreach(action, net_modified_set) {
+
+    if (GENERIC_LMM_ACTION(action).suspended != 0) {
+      continue;
+    }
+
+    delta = now - GENERIC_LMM_ACTION(action).last_update;
+
+    double_update(&(((surf_action_t)action)->remains),
+                  lmm_variable_getvalue(((surf_action_lmm_t) action)->variable) * delta);
+
+    if (((surf_action_t)action)->max_duration != NO_MAX_DURATION)
+      double_update(&(((surf_action_t)action)->max_duration), delta);
+
+    if ((((surf_action_t)action)->remains <= 0) &&
+        (lmm_get_variable_weight(((surf_action_lmm_t)action)->variable) > 0)) {
+      ((surf_action_t)action)->finish = surf_get_clock();
+      surf_network_model->action_state_set((surf_action_t) action,
+                                           SURF_ACTION_DONE);
+      heap_remove(action);
+    } else if (((((surf_action_t)action)->max_duration != NO_MAX_DURATION)
+               && (((surf_action_t)action)->max_duration <= 0))) {
+      ((surf_action_t)action)->finish = surf_get_clock();
+      surf_network_model->action_state_set((surf_action_t) action,
+                                           SURF_ACTION_DONE);
+      heap_remove(action);
+    }
+
+    GENERIC_LMM_ACTION(action).last_update = now;
+  }
+}
+
+static double net_share_resources_full(double now)
+{
+  s_surf_action_lmm_t s_action;
   surf_action_network_CM02_t action = NULL;
   xbt_swag_t running_actions =
       surf_network_model->states.running_action_set;
@@ -406,16 +442,13 @@ static double net_share_resources(double now)
   xbt_swag_foreach(action, running_actions) {
 #ifdef HAVE_LATENCY_BOUND_TRACKING
     if (lmm_is_variable_limited_by_latency(action->variable)) {
-      (action->generic_action).latency_limited = 1;
+      GENERIC_LMM_ACTION(action).latency_limited = 1;
     } else {
-      (action->generic_action).latency_limited = 0;
+      GENERIC_LMM_ACTION(action).latency_limited = 0;
     }
 #endif
     if (action->latency > 0) {
-      if (min < 0)
-        min = action->latency;
-      else if (action->latency < min)
-        min = action->latency;
+      min = (min < 0) ? action->latency : min(min, action->latency);
     }
   }
 
@@ -424,7 +457,79 @@ static double net_share_resources(double now)
   return min;
 }
 
-static void net_update_actions_state(double now, double delta)
+static double net_share_resources_lazy(double now)
+{
+  surf_action_network_CM02_t action = NULL;
+  double min = -1;
+  double value;
+
+  XBT_DEBUG
+      ("Before share resources, the size of modified actions set is %d",
+       xbt_swag_size(net_modified_set));
+  update_action_remaining_lazy(now);
+
+  lmm_solve(network_maxmin_system);
+
+  XBT_DEBUG
+      ("After share resources, The size of modified actions set is %d",
+       xbt_swag_size(net_modified_set));
+
+  xbt_swag_foreach(action, net_modified_set) {
+    int max_dur_flag = 0;
+
+    if (GENERIC_ACTION(action).state_set !=
+        surf_network_model->states.running_action_set)
+      continue;
+
+    /* bogus priority, skip it */
+    if (GENERIC_ACTION(action).priority <= 0)
+      continue;
+
+    min = -1;
+    value = lmm_variable_getvalue(GENERIC_LMM_ACTION(action).variable);
+    if (value > 0) {
+      if (GENERIC_ACTION(action).remains > 0) {
+        value = GENERIC_ACTION(action).remains / value;
+        min = now + value;
+      } else {
+        value = 0.0;
+        min = now;
+      }
+    }
+
+    if ((GENERIC_ACTION(action).max_duration != NO_MAX_DURATION)
+        && (min == -1
+            || GENERIC_ACTION(action).start +
+            GENERIC_ACTION(action).max_duration < min)) {
+      min = GENERIC_ACTION(action).start +
+          GENERIC_ACTION(action).max_duration;
+      max_dur_flag = 1;
+    }
+
+    XBT_DEBUG("Action(%p) Start %lf Finish %lf Max_duration %lf", action,
+              GENERIC_ACTION(action).start, now + value,
+              GENERIC_ACTION(action).max_duration);
+
+    if (min != -1) {
+      heap_remove(action);
+      heap_insert(action, min, max_dur_flag ? MAX_DURATION : NORMAL);
+      XBT_DEBUG("Insert at heap action(%p) min %lf now %lf", action, min,
+                now);
+    } else DIE_IMPOSSIBLE;
+  }
+
+  //hereafter must have already the min value for this resource model
+  if (xbt_heap_size(net_action_heap) > 0)
+    min = xbt_heap_maxkey(net_action_heap) - now;
+  else
+    min = -1;
+
+  XBT_DEBUG("The minimum with the HEAP %lf", min);
+
+  return min;
+}
+
+static void net_update_actions_state_full(double now, double delta)
 {
   double deltap = 0.0;
   surf_action_network_CM02_t action = NULL;
@@ -446,57 +551,94 @@ static void net_update_actions_state(double now, double delta)
         double_update(&(deltap), action->latency);
         action->latency = 0.0;
       }
-      if ((action->latency == 0.0) && !(action->suspended))
-        lmm_update_variable_weight(network_maxmin_system, action->variable,
+      if ((action->latency == 0.0) && !(GENERIC_LMM_ACTION(action).suspended))
+        lmm_update_variable_weight(network_maxmin_system, GENERIC_LMM_ACTION(action).variable,
                                    action->weight);
     }
 #ifdef HAVE_TRACING
     if (TRACE_is_enabled()) {
-      xbt_dynar_t route = global_routing->get_route(action->src_name,
-                                                    action->dst_name);
+      xbt_dynar_t route = NULL;
+      routing_get_route_and_latency(action->src_name, action->dst_name,
+                                    &route, NULL);
       link_CM02_t link;
       unsigned int i;
       xbt_dynar_foreach(route, i, link) {
-        TRACE_surf_link_set_utilization(link->lmm_resource.generic_resource.name,
-                                        action->generic_action.data,
-                                        (surf_action_t) action,
-                                        lmm_variable_getvalue
-                                        (action->variable), now - delta,
-                                        delta);
+        TRACE_surf_link_set_utilization(link->lmm_resource.
+            generic_resource.name,
+            GENERIC_ACTION(action).data,
+            (surf_action_t) action,
+            lmm_variable_getvalue(GENERIC_LMM_ACTION(action).variable),
+            now - delta, delta);
       }
     }
 #endif
-    if(!lmm_get_number_of_cnst_from_var(network_maxmin_system, action->variable)) {
-                               /* There is actually no link used, hence an infinite bandwidth.
-                                * This happens often when using models like vivaldi.
-                                * In such case, just make sure that the action completes immediately.
-                                */
-       double_update(&(action->generic_action.remains),
-                       action->generic_action.remains);
+    if (!lmm_get_number_of_cnst_from_var
+        (network_maxmin_system, GENERIC_LMM_ACTION(action).variable)) {
+      /* There is actually no link used, hence an infinite bandwidth.
+       * This happens often when using models like vivaldi.
+       * In such case, just make sure that the action completes immediately.
+       */
+      double_update(&(GENERIC_ACTION(action).remains),
+                    GENERIC_ACTION(action).remains);
     }
-    double_update(&(action->generic_action.remains),
-                  lmm_variable_getvalue(action->variable) * deltap);
-    if (action->generic_action.max_duration != NO_MAX_DURATION)
-      double_update(&(action->generic_action.max_duration), delta);
-
-    if ((action->generic_action.remains <= 0) &&
-        (lmm_get_variable_weight(action->variable) > 0)) {
-      action->generic_action.finish = surf_get_clock();
+    double_update(&(GENERIC_ACTION(action).remains),
+                  lmm_variable_getvalue(GENERIC_LMM_ACTION(action).variable) * deltap);
+    if (((surf_action_t)action)->max_duration != NO_MAX_DURATION)
+      double_update(&(((surf_action_t)action)->max_duration), delta);
+
+    if ((GENERIC_ACTION(action).remains <= 0) &&
+        (lmm_get_variable_weight(GENERIC_LMM_ACTION(action).variable) > 0)) {
+      ((surf_action_t)action)->finish = surf_get_clock();
       surf_network_model->action_state_set((surf_action_t) action,
                                            SURF_ACTION_DONE);
-      gap_remove(action);
-    } else if ((action->generic_action.max_duration != NO_MAX_DURATION)
-               && (action->generic_action.max_duration <= 0)) {
-      action->generic_action.finish = surf_get_clock();
+
+      if (gap_remove)
+        gap_remove(action);
+    } else if ((((surf_action_t)action)->max_duration != NO_MAX_DURATION)
+               && (((surf_action_t)action)->max_duration <= 0)) {
+      ((surf_action_t)action)->finish = surf_get_clock();
       surf_network_model->action_state_set((surf_action_t) action,
                                            SURF_ACTION_DONE);
-      gap_remove(action);
+      if (gap_remove)
+        gap_remove(action);
     }
   }
 
   return;
 }
 
+static void net_update_actions_state_lazy(double now, double delta)
+{
+  surf_action_network_CM02_t action = NULL;
+
+  while ((xbt_heap_size(net_action_heap) > 0)
+         && (double_equals(xbt_heap_maxkey(net_action_heap), now))) {
+    action = xbt_heap_pop(net_action_heap);
+    XBT_DEBUG("Action %p: finish", action);
+    GENERIC_ACTION(action).finish = surf_get_clock();
+
+    // if I am wearing a latency hat
+    if (GENERIC_LMM_ACTION(action).hat == LATENCY) {
+      lmm_update_variable_weight(network_maxmin_system, GENERIC_LMM_ACTION(action).variable,
+                                 action->weight);
+      heap_remove(action);
+      GENERIC_LMM_ACTION(action).last_update = surf_get_clock();
+
+      // if I am wearing a max_duration or normal hat
+    } else if (GENERIC_LMM_ACTION(action).hat == MAX_DURATION ||
+        GENERIC_LMM_ACTION(action).hat == NORMAL) {
+      // no need to communicate anymore
+      // assume that flows that reached max_duration have remaining of 0
+      GENERIC_ACTION(action).remains = 0;
+      ((surf_action_t)action)->finish = surf_get_clock();
+      surf_network_model->action_state_set((surf_action_t) action,
+                                           SURF_ACTION_DONE);
+      heap_remove(action);
+    }
+  }
+  return;
+}
+
 static void net_update_resource_state(void *id,
                                       tmgr_trace_event_t event_type,
                                       double value, double date)
@@ -522,7 +664,10 @@ static void net_update_resource_state(void *id,
                                 (nw_link->lmm_resource.power.peak *
                                  nw_link->lmm_resource.power.scale));
 #ifdef HAVE_TRACING
-    TRACE_surf_link_set_bandwidth(date, nw_link->lmm_resource.generic_resource.name,
+    TRACE_surf_link_set_bandwidth(date,
+                                  (char
+                                   *) (((nw_link->lmm_resource).
+                                        generic_resource).name),
                                   sg_bandwidth_factor *
                                   (nw_link->lmm_resource.power.peak *
                                    nw_link->lmm_resource.power.scale));
@@ -533,9 +678,9 @@ static void net_update_resource_state(void *id,
                &elem))) {
         action = lmm_variable_id(var);
         action->weight += delta;
-        if (!(action->suspended))
+        if (!(GENERIC_LMM_ACTION(action).suspended))
           lmm_update_variable_weight(network_maxmin_system,
-                                     action->variable, action->weight);
+                                     GENERIC_LMM_ACTION(action).variable, action->weight);
       }
     }
     if (tmgr_trace_event_free(event_type))
@@ -554,24 +699,25 @@ static void net_update_resource_state(void *id,
       action->lat_current += delta;
       action->weight += delta;
       if (action->rate < 0)
-        lmm_update_variable_bound(network_maxmin_system, action->variable,
+        lmm_update_variable_bound(network_maxmin_system, GENERIC_LMM_ACTION(action).variable,
                                   sg_tcp_gamma / (2.0 *
                                                   action->lat_current));
       else {
-        lmm_update_variable_bound(network_maxmin_system, action->variable,
+        lmm_update_variable_bound(network_maxmin_system, GENERIC_LMM_ACTION(action).variable,
                                   min(action->rate,
                                       sg_tcp_gamma / (2.0 *
-                                                      action->lat_current)));
+                                                      action->
+                                                      lat_current)));
 
         if (action->rate < sg_tcp_gamma / (2.0 * action->lat_current)) {
           XBT_INFO("Flow is limited BYBANDWIDTH");
         } else {
           XBT_INFO("Flow is limited BYLATENCY, latency of flow is %f",
-                action->lat_current);
+                   action->lat_current);
         }
       }
-      if (!(action->suspended))
-        lmm_update_variable_weight(network_maxmin_system, action->variable,
+      if (!(GENERIC_LMM_ACTION(action).suspended))
+        lmm_update_variable_weight(network_maxmin_system, GENERIC_LMM_ACTION(action).variable,
                                    action->weight);
 
     }
@@ -604,6 +750,9 @@ static void net_update_resource_state(void *id,
     xbt_abort();
   }
 
+  XBT_DEBUG
+      ("There were a resource state event, need to update actions related to the constraint (%p)",
+       nw_link->lmm_resource.constraint);
   return;
 }
 
@@ -617,30 +766,18 @@ static surf_action_t net_communicate(const char *src_name,
   int failed = 0;
   surf_action_network_CM02_t action = NULL;
   double bandwidth_bound;
-  double latency=0.0;
-  /* LARGE PLATFORMS HACK:
-     Add a link_CM02_t *link and a int link_nb to network_card_CM02_t. It will represent local links for this node
-     Use the cluster_id for ->id */
-
+  double latency = 0.0;
   xbt_dynar_t back_route = NULL;
   int constraints_per_variable = 0;
-  xbt_dynar_t route;
-  // I will need this route for some time so require for no cleanup
-  global_routing->get_route_latency(src_name, dst_name, &route, &latency, 0);
 
-  if (sg_network_fullduplex == 1) {
-    back_route = global_routing->get_route(dst_name, src_name);
-  }
-
-  /* LARGE PLATFORMS HACK:
-     total_route_size = route_size + src->link_nb + dst->nb */
+  xbt_dynar_t route = xbt_dynar_new(global_routing->size_of_link, NULL);
 
   XBT_IN("(%s,%s,%g,%g)", src_name, dst_name, size, rate);
-  /* LARGE PLATFORMS HACK:
-     assert on total_route_size */
-  xbt_assert(xbt_dynar_length(route) || latency,
-              "You're trying to send data from %s to %s but there is no connection at all between these two hosts.",
-              src_name, dst_name);
+
+  routing_get_route_and_latency(src_name, dst_name, &route, &latency);
+  xbt_assert(!xbt_dynar_is_empty(route) || latency,
+             "You're trying to send data from %s to %s but there is no connection at all between these two hosts.",
+             src_name, dst_name);
 
   xbt_dynar_foreach(route, i, link) {
     if (link->lmm_resource.state_current == SURF_RESOURCE_OFF) {
@@ -648,103 +785,107 @@ static surf_action_t net_communicate(const char *src_name,
       break;
     }
   }
+  if (sg_network_crosstraffic == 1) {
+    routing_get_route_and_latency(dst_name, src_name, &back_route, NULL);
+    xbt_dynar_foreach(back_route, i, link) {
+      if (link->lmm_resource.state_current == SURF_RESOURCE_OFF) {
+        failed = 1;
+        break;
+      }
+    }
+  }
+
   action =
       surf_action_new(sizeof(s_surf_action_network_CM02_t), size,
                       surf_network_model, failed);
 #ifdef HAVE_LATENCY_BOUND_TRACKING
-  (action->generic_action).latency_limited = 0;
+  (GENERIC_LMM_ACTION(action)).latency_limited = 0;
 #endif
   action->weight = action->latency = latency;
 
-  xbt_swag_insert(action, action->generic_action.state_set);
+  xbt_swag_insert(action, ((surf_action_t)action)->state_set);
   action->rate = rate;
+  if (network_update_mechanism == UM_LAZY) {
+    GENERIC_LMM_ACTION(action).index_heap = -1;
+    GENERIC_LMM_ACTION(action).last_update = surf_get_clock();
+  }
 
   bandwidth_bound = -1.0;
-
+  if (sg_weight_S_parameter > 0) {
+    xbt_dynar_foreach(route, i, link) {
+      action->weight +=
+          sg_weight_S_parameter /
+          (link->lmm_resource.power.peak * link->lmm_resource.power.scale);
+    }
+  }
   xbt_dynar_foreach(route, i, link) {
-    action->weight +=
-        sg_weight_S_parameter /
+    double bb = bandwidth_factor_callback(size) *
         (link->lmm_resource.power.peak * link->lmm_resource.power.scale);
-    if (bandwidth_bound < 0.0)
-      bandwidth_bound =
-          (*bandwidth_factor_callback) (size) *
-          (link->lmm_resource.power.peak * link->lmm_resource.power.scale);
-    else
-      bandwidth_bound =
-          min(bandwidth_bound,
-              (*bandwidth_factor_callback) (size) *
-              (link->lmm_resource.power.peak *
-               link->lmm_resource.power.scale));
-  }
-  /* LARGE PLATFORMS HACK:
-     Add src->link and dst->link latencies */
+    bandwidth_bound =
+        (bandwidth_bound < 0.0) ? bb : min(bandwidth_bound, bb);
+  }
+
   action->lat_current = action->latency;
-  action->latency *= (*latency_factor_callback) (size);
+  action->latency *= latency_factor_callback(size);
   action->rate =
-      (*bandwidth_constraint_callback) (action->rate, bandwidth_bound,
-                                        size);
+      bandwidth_constraint_callback(action->rate, bandwidth_bound, size);
+  if (gap_append) {
+    xbt_assert(!xbt_dynar_is_empty(route),
+               "Using a model with a gap (e.g., SMPI) with a platform without links (e.g. vivaldi)!!!");
 
-  if(xbt_dynar_length(route) > 0) {
-    link = *(link_CM02_t*)xbt_dynar_get_ptr(route, 0);
+    link = *(link_CM02_t *) xbt_dynar_get_ptr(route, 0);
     gap_append(size, link, action);
     XBT_DEBUG("Comm %p: %s -> %s gap=%f (lat=%f)",
-           action, src_name, dst_name, action->sender.gap, action->latency);
-  } else {
-    gap_unknown(action);
+              action, src_name, dst_name, action->sender.gap,
+              action->latency);
   }
 
+  constraints_per_variable = xbt_dynar_length(route);
+  if (back_route != NULL)
+    constraints_per_variable += xbt_dynar_length(back_route);
 
-  /* LARGE PLATFORMS HACK:
-     lmm_variable_new(..., total_route_size) */
-  if (back_route != NULL) {
-    constraints_per_variable =
-        xbt_dynar_length(route) + xbt_dynar_length(back_route);
-  } else {
-    constraints_per_variable = xbt_dynar_length(route);
-  }
-
-  if (action->latency > 0)
-    action->variable =
+  if (action->latency > 0) {
+    GENERIC_LMM_ACTION(action).variable =
         lmm_variable_new(network_maxmin_system, action, 0.0, -1.0,
                          constraints_per_variable);
-  else
-    action->variable =
+    if (network_update_mechanism == UM_LAZY) {
+      // add to the heap the event when the latency is payed
+      XBT_DEBUG("Added action (%p) one latency event at date %f", action,
+                action->latency + GENERIC_LMM_ACTION(action).last_update);
+      heap_insert(action, action->latency + GENERIC_LMM_ACTION(action).last_update,
+                  xbt_dynar_is_empty(route) ? NORMAL : LATENCY);
+    }
+  } else
+    GENERIC_LMM_ACTION(action).variable =
         lmm_variable_new(network_maxmin_system, action, 1.0, -1.0,
                          constraints_per_variable);
 
   if (action->rate < 0) {
-    if (action->lat_current > 0)
-      lmm_update_variable_bound(network_maxmin_system, action->variable,
-                                sg_tcp_gamma / (2.0 *
-                                                action->lat_current));
-    else
-      lmm_update_variable_bound(network_maxmin_system, action->variable,
-                                -1.0);
+    lmm_update_variable_bound(network_maxmin_system, GENERIC_LMM_ACTION(action).variable,
+                              (action->lat_current > 0) ?
+                              sg_tcp_gamma / (2.0 *
+                                              action->lat_current) : -1.0);
   } else {
-    if (action->lat_current > 0)
-      lmm_update_variable_bound(network_maxmin_system, action->variable,
-                                min(action->rate,
-                                    sg_tcp_gamma / (2.0 *
-                                                    action->lat_current)));
-    else
-      lmm_update_variable_bound(network_maxmin_system, action->variable,
-                                action->rate);
+    lmm_update_variable_bound(network_maxmin_system, GENERIC_LMM_ACTION(action).variable,
+                              (action->lat_current > 0) ?
+                              min(action->rate,
+                                  sg_tcp_gamma / (2.0 *
+                                                  action->lat_current))
+                              : action->rate);
   }
 
   xbt_dynar_foreach(route, i, link) {
     lmm_expand(network_maxmin_system, link->lmm_resource.constraint,
-               action->variable, 1.0);
+               GENERIC_LMM_ACTION(action).variable, 1.0);
   }
 
-  if (sg_network_fullduplex == 1) {
-    XBT_DEBUG("Fullduplex active adding backward flow using 5%c", '%');
+  if (sg_network_crosstraffic == 1) {
+    XBT_DEBUG("Fullduplex active adding backward flow using 5%%");
     xbt_dynar_foreach(back_route, i, link) {
       lmm_expand(network_maxmin_system, link->lmm_resource.constraint,
-                 action->variable, .05);
+                 GENERIC_LMM_ACTION(action).variable, .05);
     }
   }
-  /* LARGE PLATFORMS HACK:
-     expand also with src->link and dst->link */
 #ifdef HAVE_TRACING
   if (TRACE_is_enabled()) {
     action->src_name = xbt_strdup(src_name);
@@ -762,7 +903,9 @@ static surf_action_t net_communicate(const char *src_name,
 
 static xbt_dynar_t net_get_route(const char *src, const char *dst)
 {
-  return global_routing->get_route(src, dst);
+  xbt_dynar_t route = NULL;
+  routing_get_route_and_latency(src, dst, &route, NULL);
+  return route;
 }
 
 static double net_get_link_bandwidth(const void *link)
@@ -784,38 +927,46 @@ static int net_link_shared(const void *link)
 
 static void net_action_suspend(surf_action_t action)
 {
-  ((surf_action_network_CM02_t) action)->suspended = 1;
+  ((surf_action_network_CM02_t) action)->generic_lmm_action.suspended = 1;
   lmm_update_variable_weight(network_maxmin_system,
                              ((surf_action_network_CM02_t)
-                              action)->variable, 0.0);
+                              action)->generic_lmm_action.variable, 0.0);
+
+  if (network_update_mechanism == UM_LAZY)      // remove action from the heap
+    heap_remove((surf_action_network_CM02_t) action);
 }
 
 static void net_action_resume(surf_action_t action)
 {
-  if (((surf_action_network_CM02_t) action)->suspended) {
+  if (((surf_action_network_CM02_t) action)->generic_lmm_action.suspended) {
     lmm_update_variable_weight(network_maxmin_system,
                                ((surf_action_network_CM02_t)
-                                action)->variable,
+                                action)->generic_lmm_action.variable,
                                ((surf_action_network_CM02_t)
                                 action)->weight);
-    ((surf_action_network_CM02_t) action)->suspended = 0;
+    ((surf_action_network_CM02_t) action)->generic_lmm_action.suspended = 0;
+    if (network_update_mechanism == UM_LAZY)    // remove action from the heap
+      heap_remove((surf_action_network_CM02_t) action);
   }
 }
 
 static int net_action_is_suspended(surf_action_t action)
 {
-  return ((surf_action_network_CM02_t) action)->suspended;
+  return ((surf_action_network_CM02_t) action)->generic_lmm_action.suspended;
 }
 
 void net_action_set_max_duration(surf_action_t action, double duration)
 {
   action->max_duration = duration;
+  if (network_update_mechanism == UM_LAZY)      // remove action from the heap
+    heap_remove((surf_action_network_CM02_t) action);
 }
 
 #ifdef HAVE_TRACING
-static void net_action_set_category(surf_action_t action, const char *category)
+static void net_action_set_category(surf_action_t action,
+                                    const char *category)
 {
-  action->category = xbt_strdup (category);
+  action->category = xbt_strdup(category);
 }
 #endif
 
@@ -824,14 +975,85 @@ static void net_finalize(void)
   surf_model_exit(surf_network_model);
   surf_network_model = NULL;
 
-  global_routing->finalize();
-
   lmm_system_free(network_maxmin_system);
   network_maxmin_system = NULL;
+
+  if (network_update_mechanism == UM_LAZY) {
+    xbt_heap_free(net_action_heap);
+    xbt_swag_free(net_modified_set);
+  }
+
+  if (smpi_bw_factor)
+    xbt_dynar_free(&smpi_bw_factor);
+  if (smpi_lat_factor)
+    xbt_dynar_free(&smpi_lat_factor);
+}
+
+static void smpi_gap_append(double size, const link_CM02_t link,
+                            surf_action_network_CM02_t action)
+{
+  const char *src = link->lmm_resource.generic_resource.name;
+  xbt_fifo_t fifo;
+  surf_action_network_CM02_t last_action;
+  double bw;
+
+  if (sg_sender_gap > 0.0) {
+    if (!gap_lookup) {
+      gap_lookup = xbt_dict_new();
+    }
+    fifo = (xbt_fifo_t) xbt_dict_get_or_null(gap_lookup, src);
+    action->sender.gap = 0.0;
+    if (fifo && xbt_fifo_size(fifo) > 0) {
+      /* Compute gap from last send */
+      last_action =
+          (surf_action_network_CM02_t)
+          xbt_fifo_get_item_content(xbt_fifo_get_last_item(fifo));
+      bw = net_get_link_bandwidth(link);
+      action->sender.gap =
+          last_action->sender.gap + max(sg_sender_gap,
+                                        last_action->sender.size / bw);
+      action->latency += action->sender.gap;
+    }
+    /* Append action as last send */
+    action->sender.link_name = link->lmm_resource.generic_resource.name;
+    fifo =
+        (xbt_fifo_t) xbt_dict_get_or_null(gap_lookup,
+                                          action->sender.link_name);
+    if (!fifo) {
+      fifo = xbt_fifo_new();
+      xbt_dict_set(gap_lookup, action->sender.link_name, fifo, NULL);
+    }
+    action->sender.fifo_item = xbt_fifo_push(fifo, action);
+    action->sender.size = size;
+  }
+}
+
+static void smpi_gap_remove(surf_action_network_CM02_t action)
+{
+  xbt_fifo_t fifo;
+  size_t size;
+
+  if (sg_sender_gap > 0.0 && action->sender.link_name
+      && action->sender.fifo_item) {
+    fifo =
+        (xbt_fifo_t) xbt_dict_get_or_null(gap_lookup,
+                                          action->sender.link_name);
+    xbt_fifo_remove_item(fifo, action->sender.fifo_item);
+    size = xbt_fifo_size(fifo);
+    if (size == 0) {
+      xbt_fifo_free(fifo);
+      xbt_dict_remove(gap_lookup, action->sender.link_name);
+      size = xbt_dict_length(gap_lookup);
+      if (size == 0) {
+        xbt_dict_free(&gap_lookup);
+      }
+    }
+  }
 }
 
 static void surf_network_model_init_internal(void)
 {
+  s_surf_action_network_CM02_t comm;
   surf_network_model = surf_model_init();
 
   surf_network_model->name = "network";
@@ -842,11 +1064,23 @@ static void surf_network_model_init_internal(void)
 #ifdef HAVE_LATENCY_BOUND_TRACKING
   surf_network_model->get_latency_limited = net_get_link_latency_limited;
 #endif
+#ifdef HAVE_TRACING
+  surf_network_model->set_category = net_action_set_category;
+#endif
 
   surf_network_model->model_private->resource_used = net_resource_used;
-  surf_network_model->model_private->share_resources = net_share_resources;
-  surf_network_model->model_private->update_actions_state =
-      net_update_actions_state;
+  if (network_update_mechanism == UM_LAZY) {
+    surf_network_model->model_private->share_resources =
+        net_share_resources_lazy;
+    surf_network_model->model_private->update_actions_state =
+        net_update_actions_state_lazy;
+  } else if (network_update_mechanism == UM_FULL) {
+    surf_network_model->model_private->share_resources =
+        net_share_resources_full;
+    surf_network_model->model_private->update_actions_state =
+        net_update_actions_state_full;
+  }
+
   surf_network_model->model_private->update_resource_state =
       net_update_resource_state;
   surf_network_model->model_private->finalize = net_finalize;
@@ -854,10 +1088,7 @@ static void surf_network_model_init_internal(void)
   surf_network_model->suspend = net_action_suspend;
   surf_network_model->resume = net_action_resume;
   surf_network_model->is_suspended = net_action_is_suspended;
-  surf_network_model->set_max_duration = net_action_set_max_duration;
-#ifdef HAVE_TRACING
-  surf_network_model->set_category = net_action_set_category;
-#endif
+  surf_cpu_model->set_max_duration = net_action_set_max_duration;
 
   surf_network_model->extension.network.communicate = net_communicate;
   surf_network_model->extension.network.get_route = net_get_route;
@@ -871,61 +1102,113 @@ static void surf_network_model_init_internal(void)
       net_create_resource;
 
   if (!network_maxmin_system)
-    network_maxmin_system = lmm_system_new();
+    network_maxmin_system = lmm_system_new(net_selective_update);
 
   routing_model_create(sizeof(link_CM02_t),
-                       net_link_new(xbt_strdup("__loopback__"),
-                                    498000000, NULL, 0.000015, NULL,
-                                    SURF_RESOURCE_ON, NULL,
-                                    SURF_LINK_FATPIPE, NULL),
-                      net_get_link_latency);
+                       net_create_resource("__loopback__",
+                                           498000000, NULL, 0.000015, NULL,
+                                           SURF_RESOURCE_ON, NULL,
+                                           SURF_LINK_FATPIPE, NULL));
+
+  if (network_update_mechanism == UM_LAZY) {
+    net_action_heap = xbt_heap_new(8, NULL);
+    xbt_heap_set_update_callback(net_action_heap,
+                                 net_action_update_index_heap);
+    net_modified_set =
+        xbt_swag_new(xbt_swag_offset(comm, generic_lmm_action.action_list_hookup));
+    network_maxmin_system->keep_track = net_modified_set;
+  }
 }
 
+static void set_update_mechanism(void)
+{
+#ifdef HAVE_TRACING
+  TRACE_set_network_update_mechanism();
+#endif
 
+  char *optim = xbt_cfg_get_string(_surf_cfg_set, "network/optim");
+  int select =
+      xbt_cfg_get_int(_surf_cfg_set, "network/maxmin_selective_update");
+
+  if (!strcmp(optim, "Full")) {
+    network_update_mechanism = UM_FULL;
+    net_selective_update = select;
+  } else if (!strcmp(optim, "Lazy")) {
+    network_update_mechanism = UM_LAZY;
+    net_selective_update = 1;
+    xbt_assert((select == 1)
+               ||
+               (xbt_cfg_is_default_value
+                (_surf_cfg_set, "network/maxmin_selective_update")),
+               "Disabling selective update while using the lazy update mechanism is dumb!");
+  } else {
+    xbt_die("Unsupported optimization (%s) for this model", optim);
+  }
+}
 
 /************************************************************************/
 /* New model based on LV08 and experimental results of MPI ping-pongs   */
 /************************************************************************/
-void surf_network_model_init_SMPI(const char *filename)
+/* @Inproceedings{smpi_ipdps, */
+/*  author={Pierre-Nicolas Clauss and Mark Stillwell and Stéphane Genaud and Frédéric Suter and Henri Casanova and Martin Quinson}, */
+/*  title={Single Node On-Line Simulation of {MPI} Applications with SMPI}, */
+/*  booktitle={25th IEEE International Parallel and Distributed Processing Symposium (IPDPS'11)}, */
+/*  address={Anchorage (Alaska) USA}, */
+/*  month=may, */
+/*  year={2011} */
+/*  } */
+void surf_network_model_init_SMPI(void)
 {
 
   if (surf_network_model)
     return;
+  set_update_mechanism();
+
   surf_network_model_init_internal();
   latency_factor_callback = &smpi_latency_factor;
   bandwidth_factor_callback = &smpi_bandwidth_factor;
   bandwidth_constraint_callback = &smpi_bandwidth_constraint;
-  net_define_callbacks(filename);
+  gap_append = &smpi_gap_append;
+  gap_remove = &smpi_gap_remove;
+  net_define_callbacks();
   xbt_dynar_push(model_list, &surf_network_model);
   network_solve = lmm_solve;
 
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/sender_gap", 10e-6);
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/weight_S", 8775);
-
-  update_model_description(surf_network_model_description,
-                           "SMPI", surf_network_model);
 }
 
 /************************************************************************/
-/* New model based on optimizations discussed during this thesis        */
+/* New model based on optimizations discussed during Pedro Velho's thesis*/
 /************************************************************************/
-void surf_network_model_init_LegrandVelho(const char *filename)
+/* @techreport{VELHO:2011:HAL-00646896:1, */
+/*      url = {http://hal.inria.fr/hal-00646896/en/}, */
+/*      title = {{Flow-level network models: have we reached the limits?}}, */
+/*      author = {Velho, Pedro and Schnorr, Lucas and Casanova, Henri and Legrand, Arnaud}, */
+/*      type = {Rapport de recherche}, */
+/*      institution = {INRIA}, */
+/*      number = {RR-7821}, */
+/*      year = {2011}, */
+/*      month = Nov, */
+/*      pdf = {http://hal.inria.fr/hal-00646896/PDF/rr-validity.pdf}, */
+/*  } */
+void surf_network_model_init_LegrandVelho(void)
 {
-
   if (surf_network_model)
     return;
+
+  set_update_mechanism();
+
   surf_network_model_init_internal();
-  net_define_callbacks(filename);
+  net_define_callbacks();
   xbt_dynar_push(model_list, &surf_network_model);
   network_solve = lmm_solve;
 
-  xbt_cfg_setdefault_double(_surf_cfg_set, "network/latency_factor", 10.4);
+  xbt_cfg_setdefault_double(_surf_cfg_set, "network/latency_factor",
+                            13.01);
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/bandwidth_factor",
-                            0.92);
-  xbt_cfg_setdefault_double(_surf_cfg_set, "network/weight_S", 8775);
-
-  update_model_description(surf_network_model_description,
-                           "LV08", surf_network_model);
+                            0.97);
+  xbt_cfg_setdefault_double(_surf_cfg_set, "network/weight_S", 20537);
 }
 
 /***************************************************************************/
@@ -939,26 +1222,42 @@ void surf_network_model_init_LegrandVelho(const char *filename)
 /*   month         = {oct}, */
 /*   year          = {2002} */
 /* } */
-void surf_network_model_init_CM02(const char *filename)
+void surf_network_model_init_CM02(void)
 {
 
   if (surf_network_model)
     return;
+
+  set_update_mechanism();
   surf_network_model_init_internal();
-  net_define_callbacks(filename);
+  net_define_callbacks();
   xbt_dynar_push(model_list, &surf_network_model);
   network_solve = lmm_solve;
 
-  update_model_description(surf_network_model_description,
-                           "CM02", surf_network_model);
+  xbt_cfg_setdefault_double(_surf_cfg_set, "network/latency_factor", 1.0);
+  xbt_cfg_setdefault_double(_surf_cfg_set, "network/bandwidth_factor",
+                            1.0);
+  xbt_cfg_setdefault_double(_surf_cfg_set, "network/weight_S", 0.0);
 }
 
-void surf_network_model_init_Reno(const char *filename)
+/***************************************************************************/
+/* The models from Steven H. Low                                           */
+/***************************************************************************/
+/* @article{Low03,                                                         */
+/*   author={Steven H. Low},                                               */
+/*   title={A Duality Model of {TCP} and Queue Management Algorithms},     */
+/*   year={2003},                                                          */
+/*   journal={{IEEE/ACM} Transactions on Networking},                      */
+/*    volume={11}, number={4},                                             */
+/*  }                                                                      */
+void surf_network_model_init_Reno(void)
 {
   if (surf_network_model)
     return;
+
+  set_update_mechanism();
   surf_network_model_init_internal();
-  net_define_callbacks(filename);
+  net_define_callbacks();
 
   xbt_dynar_push(model_list, &surf_network_model);
   lmm_set_default_protocol_function(func_reno_f, func_reno_fp,
@@ -969,18 +1268,17 @@ void surf_network_model_init_Reno(const char *filename)
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/bandwidth_factor",
                             0.92);
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/weight_S", 8775);
-
-  update_model_description(surf_network_model_description,
-                           "Reno", surf_network_model);
 }
 
 
-void surf_network_model_init_Reno2(const char *filename)
+void surf_network_model_init_Reno2(void)
 {
   if (surf_network_model)
     return;
+
+  set_update_mechanism();
   surf_network_model_init_internal();
-  net_define_callbacks(filename);
+  net_define_callbacks();
 
   xbt_dynar_push(model_list, &surf_network_model);
   lmm_set_default_protocol_function(func_reno2_f, func_reno2_fp,
@@ -992,17 +1290,16 @@ void surf_network_model_init_Reno2(const char *filename)
                             0.92);
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/weight_S_parameter",
                             8775);
-
-  update_model_description(surf_network_model_description,
-                           "Reno2", surf_network_model);
 }
 
-void surf_network_model_init_Vegas(const char *filename)
+void surf_network_model_init_Vegas(void)
 {
   if (surf_network_model)
     return;
+
+  set_update_mechanism();
   surf_network_model_init_internal();
-  net_define_callbacks(filename);
+  net_define_callbacks();
 
   xbt_dynar_push(model_list, &surf_network_model);
   lmm_set_default_protocol_function(func_vegas_f, func_vegas_fp,
@@ -1013,7 +1310,4 @@ void surf_network_model_init_Vegas(const char *filename)
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/bandwidth_factor",
                             0.92);
   xbt_cfg_setdefault_double(_surf_cfg_set, "network/weight_S", 8775);
-
-  update_model_description(surf_network_model_description,
-                           "Vegas", surf_network_model);
 }