X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/loba.git/blobdiff_plain/7b62c7947835062683a092b95e52ca2a560a14e8..cb0554d856608cef6bf4c6d92f9b26f203cc97a8:/loba_bulk.cpp

diff --git a/loba_bulk.cpp b/loba_bulk.cpp
index 9af50cf..0821eda 100644
--- a/loba_bulk.cpp
+++ b/loba_bulk.cpp
@@ -1,3 +1,4 @@
+#include <cmath>
 #include <xbt/log.h>
 
 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(loba);
@@ -6,8 +7,81 @@ XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(loba);
 
 void loba_bulk::load_balance()
 {
-    // write code here...
-    xbt_die("Load-balancing algorithm \"bulk\" not implemented!");
+	float myLoad = get_load();
+
+	unsigned NbNwMinLoad = 0;
+	unsigned NbNwLowerLoad = 0;
+	unsigned NbNeighbours = pneigh.size();
+
+	double *S = new double[NbNeighbours];
+	for (unsigned i = 0; i < NbNeighbours; i++)
+		S[i] = 0.0;
+	//What is the minimum and maximum load under myLoad?
+	float minLoad = myLoad;
+	for (unsigned i = 0; i < NbNeighbours; i++) {
+		if (pneigh[i]->get_load() < minLoad) {
+			minLoad = pneigh[i]->get_load();
+		}
+		if (pneigh[i]->get_load() < myLoad) {
+			NbNwLowerLoad++;
+		}
+	}
+	for (unsigned i = 0; i < NbNeighbours; i++)
+		if (pneigh[i]->get_load() == minLoad)
+			NbNwMinLoad++;
+
+	float maxLoad = minLoad;
+	for (unsigned i = 0; i < NbNeighbours; i++) {
+		if (pneigh[i]->get_load() > minLoad && pneigh[i]->get_load() < myLoad)
+			if (maxLoad < pneigh[i]->get_load())
+				maxLoad = pneigh[i]->get_load();
+	}
+
+	double alpha = 0.0;
+
+	if (NbNwLowerLoad && NbNwMinLoad < NbNwLowerLoad) //There is one or many neighbors with minimum load but not all neighbors have minimum load
+		alpha = (1. / ((double) NbNwMinLoad + 2));
+	if (NbNwMinLoad == NbNwLowerLoad) //All neighbors have minimum load
+		alpha = (1. / ((double) NbNwMinLoad + 1));
+	float myS = 0.;
+	//There exist underloaded neighbors
+	if (NbNwMinLoad && myLoad != 0.0) {
+		for (unsigned i = 0; i < NbNeighbours; i++) {
+			if (pneigh[i]->get_load() == minLoad) {
+				S[i] = floor(alpha * (myLoad - minLoad));
+				myS +=  S[i];
+			} else {
+				if (pneigh[i]->get_load() < myLoad) {
+					S[i] = floor(alpha * (myLoad - pneigh[i]->get_load()));
+					myS +=  S[i];
+				}
+			}
+		}
+		//Check assumption 4.2 (b) page 520
+		bool HaveToCorrectS = false;
+		for (unsigned i = 0; i < NbNeighbours; i++) {
+			if (pneigh[i]->get_load() < myLoad) { //
+				//Condition 4.6
+				if ((myLoad - myS) < (pneigh[i]->get_load() + S[i])) {
+					HaveToCorrectS = true;
+				}
+			}
+		}
+		if (HaveToCorrectS) {
+				for (unsigned i = 0; i < NbNeighbours; i++) {
+					while (((myLoad - myS) < pneigh[i]->get_load() + S[i]) && (S[i] > 0)) {
+						myS -= 1.0;
+						S[i] -= 1.0;
+					}
+				}
+		}
+	}//End there are underloaded neighbors;
+	for (unsigned i = 0 ; i < NbNeighbours ; i++) {
+                send(pneigh[i], S[i]);
+                XBT_DEBUG("sent to %s", pneigh[i]->get_name());
+        }
+
+	delete[] S;
 }
 
 // Local variables: