diff --git a/scripts/count_violations.sh b/scripts/count_violations.sh
new file mode 100644
index 0000000..f182b75
--- /dev/null
+++ b/scripts/count_violations.sh
@@ -0,0 +1,49 @@
+#!/bin/bash
+
+#---------------------------------------------------------------------
+#
+#    Copyright (C) 2015- by Tiziano De Matteis (dematteis <at> di.unipi.it)
+#
+#    This file is part of elastic-hft.
+#
+#    elastic-hft is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License as published by
+#    the Free Software Foundation, either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU General Public License for more details.
+#
+#    You should have received a copy of the GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+#    ---------------------------------------------------------------------
+# Count the number of violations taking in input a directory containing the stats files
+# e.g. generated with conf_interval_real or conf_interval_synthetic scripts
+
+if [ -z "$1" ]; then
+	echo "Specify the directory containing the stat files as first command line argument"
+	exit 1
+fi
+
+if [ -z "$2" ]; then
+	echo "Specify the latency threshold (in usecs) as second command line argument"
+	exit 1
+fi
+
+if [ ! -d "$1" ]; then
+  echo "The directory $1 does not exists!"
+  exit 1
+fi
+
+
+for stat_file in $1/stat*dat
+do
+	tail -n +2 $stat_file | head -n -2 | cut -f 3 | awk -v thr=$2 'BEGIN {count=0} {if($1>thr){count++}} END{print count;}' >> tmp_violations
+done
+
+
+cat tmp_violations | awk 'BEGIN{sum=0; count=0;} {sum+=$1; count++;} END {print "Average #violations: "sum/count;}'
+rm tmp_violations;
diff --git a/src/utils.cpp b/src/utils.cpp
index 1337ee2..36d300b 100644
--- a/src/utils.cpp
+++ b/src/utils.cpp
@@ -99,14 +99,19 @@ std::vector<int>* getCoreIDs()
         num_virt_cores+= cpu->getVirtualCores().size();
      }
      std::vector<int> *core_ids=new std::vector<int>();
-
-     std::vector<VirtualCore*> virtualCores = topology->getVirtualCores();
+     std::vector<PhysicalCore*> physicalCores= topology->getPhysicalCores();
 
      //now take the id of one virtual core per physical core;
      //assuming that physical core are number starting from zero
-     int curr_phys_core=0;
      bool constantTSC=true;
-     for(size_t i = 0; i < virtualCores.size(); i++)
+     for(size_t i=0;i<physicalCores.size();i++)
+     {
+         PhysicalCore* pc=(physicalCores.at(i));
+         core_ids->push_back(pc->getVirtualCore()->getVirtualCoreId());
+         if(!pc->getVirtualCore()->areTicksConstant())
+             constantTSC=false;
+     }
+    /* for(size_t i = 0; i < virtualCores.size(); i++)
      {
        VirtualCore* vc = virtualCores.at(i);
        if(vc->getPhysicalCoreId()==curr_phys_core)
@@ -116,7 +121,7 @@ std::vector<int>* getCoreIDs()
        }
        if(!vc->areTicksConstant())
            constantTSC=false;
-     }
+     }*/
      if(!constantTSC)
          std::cout<< "ATTENTION: the machine has not constant TSC. The program may not work since relies on this to get accurate timings" <<std::endl;
      return core_ids;