diff --git a/libsrc/meshing/bisect.cpp b/libsrc/meshing/bisect.cpp
index f26b1175..ea61b872 100644
--- a/libsrc/meshing/bisect.cpp
+++ b/libsrc/meshing/bisect.cpp
@@ -3622,7 +3622,7 @@ namespace netgen
     mtris.SetAllocSize (mtris.Size());
     mquads.SetAllocSize (mquads.Size());
   
-    
+    (*opt.tracer)("copy tets", false);
     mesh.ClearVolumeElements();
     mesh.VolumeElements().SetAllocSize (mtets.Size()+mprisms.Size());
     for (int i = 1; i <= mtets.Size(); i++)
@@ -3634,6 +3634,8 @@ namespace netgen
 	el.SetOrder (mtets.Get(i).order);
 	mesh.AddVolumeElement (el);
       }
+    (*opt.tracer)("copy tets", true);
+    
     for (int i = 1; i <= mprisms.Size(); i++)
       {
 	Element el(PRISM);
@@ -3845,7 +3847,10 @@ namespace netgen
 
 
     mesh.ComputeNVertices();
+
+    (*opt.tracer)("call RebuildSurfElList", false);
     mesh.RebuildSurfaceElementLists();
+    (*opt.tracer)("call RebuildSurfElList", true);
   
     
     // update identification tables
@@ -4027,7 +4032,7 @@ namespace netgen
 
     NgProfiler::StartTimer (timer3a);
     (*opt.tracer)("topology from bisect", false);
-    mesh.UpdateTopology(opt.task_manager);
+    mesh.UpdateTopology(opt.task_manager, opt.tracer);
     (*opt.tracer)("topology from bisect", true);
     NgProfiler::StopTimer (timer3a);    
 
diff --git a/libsrc/meshing/meshclass.cpp b/libsrc/meshing/meshclass.cpp
index 3939c4f2..01604766 100644
--- a/libsrc/meshing/meshclass.cpp
+++ b/libsrc/meshing/meshclass.cpp
@@ -5768,10 +5768,13 @@ namespace netgen
     return 1;
   }
 
-  void Mesh :: UpdateTopology (TaskManager tm)
+  void Mesh :: UpdateTopology (TaskManager tm,
+                               Tracer tracer)
   {
-    topology.Update(tm);
+    topology.Update(tm, tracer);
+    (*tracer)("call update clusters", false);
     clusters->Update(tm);
+    (*tracer)("call update clusters", true);
 #ifdef PARALLEL
     if (paralleltop)
       {
diff --git a/libsrc/meshing/meshclass.hpp b/libsrc/meshing/meshclass.hpp
index 0832fcf8..19b1e65a 100644
--- a/libsrc/meshing/meshclass.hpp
+++ b/libsrc/meshing/meshclass.hpp
@@ -705,7 +705,8 @@ namespace netgen
     const MeshTopology & GetTopology () const
     { return topology; }
 
-    DLL_HEADER void UpdateTopology (TaskManager tm = &DummyTaskManager);
+    DLL_HEADER void UpdateTopology (TaskManager tm = &DummyTaskManager,
+                                    Tracer tracer = &DummyTracer);
   
     class CurvedElements & GetCurvedElements () const
     { return *curvedelems; }
diff --git a/libsrc/meshing/topology.cpp b/libsrc/meshing/topology.cpp
index 83ed7aed..3e4ad494 100644
--- a/libsrc/meshing/topology.cpp
+++ b/libsrc/meshing/topology.cpp
@@ -4,6 +4,11 @@
 namespace netgen
 {
 
+  template<typename T>
+  inline atomic<T> & AsAtomic (T & d)
+  {
+    return reinterpret_cast<atomic<T>&> (d);
+  }
 
 
   
@@ -331,7 +336,7 @@ namespace netgen
   }
   
   
-  void MeshTopology :: Update (TaskManager tm)
+  void MeshTopology :: Update (TaskManager tm, Tracer tracer)
   {
     static int timer = NgProfiler::CreateTimer ("topology");
     NgProfiler::RegionTimer reg (timer);
@@ -358,7 +363,8 @@ namespace netgen
     (*testout) << "nseg = " << nseg << endl;
     (*testout) << "np   = " << np << endl;
     (*testout) << "nv   = " << nv << endl;
-    
+
+    (*tracer) ("Topology::Update setup tables", false);
     Array<int,PointIndex::BASE> cnt(nv);
     Array<int> vnums;
 
@@ -369,13 +375,26 @@ namespace netgen
       vertex to segment 
     */
     cnt = 0;
+    /*
     for (ElementIndex ei = 0; ei < ne; ei++)
       {
 	const Element & el = (*mesh)[ei];
 	for (int j = 0; j < el.GetNV(); j++)
 	  cnt[el[j]]++;
       }
-
+    */
+    ParallelForRange
+      (tm, ne,
+       [&] (size_t begin, size_t end)
+       {
+         for (ElementIndex ei = begin; ei < end; ei++)
+           {
+             const Element & el = (*mesh)[ei];
+             for (int j = 0; j < el.GetNV(); j++)
+               AsAtomic(cnt[el[j]])++;
+           }
+       });
+    
     vert2element = TABLE<ElementIndex,PointIndex::BASE> (cnt);
     for (ElementIndex ei = 0; ei < ne; ei++)
       {
@@ -385,12 +404,27 @@ namespace netgen
       }
 
     cnt = 0;
+    /*
     for (SurfaceElementIndex sei = 0; sei < nse; sei++)
       {
 	const Element2d & el = (*mesh)[sei];
 	for (int j = 0; j < el.GetNV(); j++)
 	  cnt[el[j]]++;
       }
+    */
+    ParallelForRange
+      (tm, nse,
+       [&] (size_t begin, size_t end)
+       {
+         for (SurfaceElementIndex ei = begin; ei < end; ei++)
+           {
+             const Element2d & el = (*mesh)[ei];
+             for (int j = 0; j < el.GetNV(); j++)
+               AsAtomic(cnt[el[j]])++;
+           }
+       });
+
+    
 
     vert2surfelement = TABLE<SurfaceElementIndex,PointIndex::BASE> (cnt);
     for (SurfaceElementIndex sei = 0; sei < nse; sei++)
@@ -430,6 +464,7 @@ namespace netgen
 	const Element0d & pointel = mesh->pointelements[pei];
 	vert2pointelement.AddSave (pointel.pnum, pei);
       }
+    (*tracer) ("Topology::Update setup tables", true);
 
     
     if (buildedges)
diff --git a/libsrc/meshing/topology.hpp b/libsrc/meshing/topology.hpp
index aca17d41..831a1ca5 100644
--- a/libsrc/meshing/topology.hpp
+++ b/libsrc/meshing/topology.hpp
@@ -83,7 +83,7 @@ public:
   bool HasFaces () const
   { return buildfaces; }
 
-  void Update(TaskManager tm = &DummyTaskManager);
+  void Update(TaskManager tm = &DummyTaskManager, Tracer tracer = &DummyTracer);
 
 
   int GetNEdges () const { return edge2vert.Size(); }