From 03a16acd38dfaa266986de5d73f4a90c0ddbfeb1 Mon Sep 17 00:00:00 2001
From: Arnaud Giersch <arnaud.giersch@iut-bm.univ-fcomte.fr>
Date: Wed, 31 Aug 2011 22:04:55 +0200
Subject: [PATCH] Enforce integer initial load when integer transfers are
 activated.

---
 BUGS           | 10 ----------
 deployment.cpp | 31 +++++++++++++++++++++++++++++--
 main.cpp       |  6 ++++++
 process.cpp    |  7 +++++++
 4 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/BUGS b/BUGS
index 3a1a2a4..040cfc3 100644
--- a/BUGS
+++ b/BUGS
@@ -1,14 +1,4 @@
 ========================================================================
-En mode entier (-Z), aucune vérification n'est faite sur la charge
-totale, ni sur la répartition initiale!
-
-Il faut vérifier, et arrondir et émettre un warning dans le cas contraire :
-- que la charge totale est entière, dans main.cpp ;
-- au début de chaque process que la charge initiale est entière.
-
-Il faut également s'assurer que la répartition aléatoire produit une
-distribution entière.
-
 ========================================================================
 ##### RESOLVED BUGS COME AFTER THIS ####################################
 ========================================================================
diff --git a/deployment.cpp b/deployment.cpp
index 8f52806..2befb00 100644
--- a/deployment.cpp
+++ b/deployment.cpp
@@ -63,8 +63,35 @@ void deployment_generator::distribute_load()
         std::accumulate(loads.begin(), loads.end(), 0.0);
     std::transform(loads.begin(), loads.end(), loads.begin(),
                    std::bind(std::multiplies<double>(), _1, factor));
-    for (unsigned i = 0 ; i < hosts.size() ; ++i)
-        set_load(i, loads[i]);
+    if (opt::integer_transfer) {
+        // round the loads
+        std::vector<double> iloads(hosts.size());
+        std::transform(loads.begin(), loads.end(), iloads.begin(), round);
+        // compute the differences between each load and its rounded value
+        std::vector<double> diffs(hosts.size());
+        std::transform(loads.begin(), loads.end(), iloads.begin(),
+                       diffs.begin(), std::minus<double>());
+        // compute the absolute values of the diffs
+        std::vector<double> adiffs(hosts.size());
+        std::transform(diffs.begin(), diffs.end(), adiffs.begin(), fabs);
+        // find i, index of the element farthest from its rounded value
+        unsigned i;
+        i = std::max_element(adiffs.begin(), adiffs.end()) - adiffs.begin();
+        // remove element i from diffs, and compute the residual part...
+        diffs[i] = diffs.back();
+        diffs.pop_back();
+        double residue = std::accumulate(diffs.begin(), diffs.end(), 0.0);
+        // ... and compute element i (rounded to avoid numerical errors)
+        iloads[i] = fabs(round(loads[i] + residue));
+        // final sanity check
+        xbt_assert(opt::auto_depl::load ==
+                   std::accumulate(iloads.begin(), iloads.end(), 0.0));
+        for (unsigned i = 0 ; i < hosts.size() ; ++i)
+            set_load(i, iloads[i]);
+    } else {
+        for (unsigned i = 0 ; i < hosts.size() ; ++i)
+            set_load(i, loads[i]);
+    }
 }
 
 void deployment_generator::deploy()
diff --git a/main.cpp b/main.cpp
index 61dfd42..80a43d9 100644
--- a/main.cpp
+++ b/main.cpp
@@ -251,6 +251,12 @@ int main(int argc, char* argv[])
             } else if (opt::auto_depl::load < 0.0)
                 opt::auto_depl::load =
                     -opt::auto_depl::load * opt::auto_depl::nhosts;
+            double iload = trunc(opt::auto_depl::load);
+            if (opt::integer_transfer && opt::auto_depl::load != iload) {
+                XBT_WARN("Total load %g is not an integer.  Truncate it.",
+                         opt::auto_depl::load);
+                opt::auto_depl::load = iload;
+            }
             MY_launch_application(); // it is already opt::* aware...
         } else {
             MSG_launch_application(opt::deployment_file.c_str());
diff --git a/process.cpp b/process.cpp
index 193c87b..e6ae2ab 100644
--- a/process.cpp
+++ b/process.cpp
@@ -37,6 +37,13 @@ process::process(int argc, char* argv[])
     if (argc < 2 || !(std::istringstream(argv[1]) >> real_load))
         throw std::invalid_argument("bad or missing initial load parameter");
 
+    double iload = trunc(real_load);
+    if (opt::integer_transfer && real_load != iload) {
+        XBT_WARN("Initial load %g is not an integer.  Truncate it.",
+                 real_load);
+        real_load = iload;
+    }
+
     neigh.assign(argv + 2, argv + argc);
 
     pneigh.reserve(neigh.size());
-- 
2.39.5