From: Arnaud Giersch <arnaud.giersch@univ-fcomte.fr>
Date: Fri, 13 Oct 2017 08:59:25 +0000 (+0200)
Subject: Repair Dijkstra's cache mode.
X-Git-Tag: v3.18~478^2
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/f7e8dd2137f34f77c8d74a71b691e54a772a84e3

Repair Dijkstra's cache mode.
---

diff --git a/src/kernel/routing/DijkstraZone.cpp b/src/kernel/routing/DijkstraZone.cpp
index 4c2d62c2bb..c6f52a0814 100644
--- a/src/kernel/routing/DijkstraZone.cpp
+++ b/src/kernel/routing/DijkstraZone.cpp
@@ -132,8 +132,6 @@ void DijkstraZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cb
   int src_id = src->id();
   int dst_id = dst->id();
 
-  int* pred_arr     = nullptr;
-  int size          = 0;
   xbt_dynar_t nodes = xbt_graph_get_nodes(routeGraph_);
 
   /* Use the graph_node id mapping set to quickly find the nodes */
@@ -162,19 +160,13 @@ void DijkstraZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cb
     }
   }
 
-  route_cache_element_t elm = nullptr;
-  if (not routeCache_.empty()) { /* cache mode  */
-    auto it = routeCache_.find(src_id);
-    elm     = (it == routeCache_.end()) ? nullptr : it->second;
-  }
-
-  if (elm) { /* cached mode and cache hit */
-    pred_arr = elm->pred_arr;
-  } else { /* not cached mode, or cache miss */
+  auto elm                   = routeCache_.emplace(src_id, std::vector<int>());
+  std::vector<int>& pred_arr = elm.first->second;
 
+  if (elm.second) { /* new element was inserted (not cached mode, or cache miss) */
     int nr_nodes      = xbt_dynar_length(nodes);
-    double* cost_arr  = new double[nr_nodes]; /* link cost from src to other hosts */
-    pred_arr          = new int[nr_nodes];    /* predecessors in path from src */
+    std::vector<double> cost_arr(nr_nodes); /* link cost from src to other hosts */
+    pred_arr.resize(nr_nodes);              /* predecessors in path from src */
     xbt_heap_t pqueue = xbt_heap_new(nr_nodes, nullptr);
 
     /* initialize */
@@ -217,8 +209,6 @@ void DijkstraZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cb
       /* free item popped from pqueue */
       delete v_id;
     }
-
-    delete[] cost_arr;
     xbt_heap_free(pqueue);
   }
 
@@ -265,7 +255,6 @@ void DijkstraZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cb
       if (lat)
         *lat += static_cast<surf::LinkImpl*>(link)->latency();
     }
-    size++;
   }
 
   if (hierarchy_ == RoutingMode::recursive) {
@@ -273,16 +262,8 @@ void DijkstraZone::getLocalRoute(NetPoint* src, NetPoint* dst, sg_platf_route_cb
     route->gw_dst = first_gw;
   }
 
-  if (not routeCache_.empty() && elm == nullptr) {
-    /* add to predecessor list of the current src-host to cache */
-    elm           = new s_route_cache_element_t;
-    elm->pred_arr = pred_arr;
-    elm->size     = size;
-    routeCache_.insert({src_id, elm});
-  }
-
-  if (routeCache_.empty())
-    delete[] pred_arr;
+  if (not cached_)
+    routeCache_.clear();
 }
 
 DijkstraZone::~DijkstraZone()
@@ -292,7 +273,7 @@ DijkstraZone::~DijkstraZone()
 
 /* Creation routing model functions */
 
-DijkstraZone::DijkstraZone(NetZone* father, std::string name, bool cached) : RoutedZone(father, name)
+DijkstraZone::DijkstraZone(NetZone* father, std::string name, bool cached) : RoutedZone(father, name), cached_(cached)
 {
 }
 
diff --git a/src/kernel/routing/DijkstraZone.hpp b/src/kernel/routing/DijkstraZone.hpp
index 5720cd6d4f..f7fc503c5e 100644
--- a/src/kernel/routing/DijkstraZone.hpp
+++ b/src/kernel/routing/DijkstraZone.hpp
@@ -14,12 +14,6 @@ struct s_graph_node_data_t {
 };
 typedef s_graph_node_data_t* graph_node_data_t;
 
-struct s_route_cache_element_t {
-  int* pred_arr;
-  int size;
-};
-typedef s_route_cache_element_t* route_cache_element_t;
-
 namespace simgrid {
 namespace kernel {
 namespace routing {
@@ -60,8 +54,9 @@ public:
   void addRoute(sg_platf_route_cbarg_t route) override;
 
   xbt_graph_t routeGraph_  = nullptr; /* xbt_graph */
-  std::map<int, xbt_node_t> graphNodeMap_;               /* map */
-  std::map<int, route_cache_element_t> routeCache_;      /* use in cache mode */
+  std::map<int, xbt_node_t> graphNodeMap_;     /* map */
+  bool cached_;                                /* cache mode */
+  std::map<int, std::vector<int>> routeCache_; /* use in cache mode */
 };
 }
 }
diff --git a/src/surf/sg_platf.cpp b/src/surf/sg_platf.cpp
index 6d5651723f..660c6db0e2 100644
--- a/src/surf/sg_platf.cpp
+++ b/src/surf/sg_platf.cpp
@@ -600,10 +600,10 @@ simgrid::s4u::NetZone* sg_platf_new_Zone_begin(ZoneCreationArgs* zone)
       new_zone = new simgrid::kernel::routing::FatTreeZone(current_routing, zone->id);
       break;
     case A_surfxml_AS_routing_Dijkstra:
-      new_zone = new simgrid::kernel::routing::DijkstraZone(current_routing, zone->id, 0);
+      new_zone = new simgrid::kernel::routing::DijkstraZone(current_routing, zone->id, false);
       break;
     case A_surfxml_AS_routing_DijkstraCache:
-      new_zone = new simgrid::kernel::routing::DijkstraZone(current_routing, zone->id, 1);
+      new_zone = new simgrid::kernel::routing::DijkstraZone(current_routing, zone->id, true);
       break;
     case A_surfxml_AS_routing_Floyd:
       new_zone = new simgrid::kernel::routing::FloydZone(current_routing, zone->id);