diff --git a/Partition.py b/Partition.py
index 5ec2df370563b0bf412550d9c87972e47187cc74..1d7b68ac32be998610662c8d43b38f11bf496940 100644
--- a/Partition.py
+++ b/Partition.py
@@ -543,3 +543,8 @@ class partition :
             ERROR("Unforessen rank for variable to summed over the core region.")
             sys.exit()
         return y
+    #
+    # Function to find max value over the entire domain
+    #
+    def domainmax(self, x) :
+        return max(self.comm.allgather(x))
diff --git a/RoutingPreProc.py b/RoutingPreProc.py
index 668a11257d2a60559fd71e9f90765f061cecd79d..9c2066ce709613430d1b82013ec2e7f2afad2be0 100644
--- a/RoutingPreProc.py
+++ b/RoutingPreProc.py
@@ -139,7 +139,7 @@ else :
 #
 nbpt = len(sub_index)
 sub_pts = np.array(list(len(sub_index[i][0]) for i in range(len(sub_index))))
-nbvmax = max(sub_pts)
+nbvmax = part.domainmax(max(sub_pts))
 print("nbpt : ", nbpt)
 print("nbvmax : ", nbvmax)
 print("nbasmax : ", nbasmax)