diff --git a/brouter-codec/src/main/java/btools/codec/MicroCache.java b/brouter-codec/src/main/java/btools/codec/MicroCache.java
index 11d547e..3dde2ae 100644
--- a/brouter-codec/src/main/java/btools/codec/MicroCache.java
+++ b/brouter-codec/src/main/java/btools/codec/MicroCache.java
@@ -55,24 +55,24 @@ public class MicroCache extends ByteDataWriter
       p2size >>= 1;
   }
 
-  public void finishNode( long id )
+  public final void finishNode( long id )
   {
     fapos[size] = aboffset;
     faid[size] = shrinkId( id );
     size++;
   }
 
-  public void discardNode()
+  public final void discardNode()
   {
     aboffset = startPos( size );
   }
 
-  public int getSize()
+  public final int getSize()
   {
     return size;
   }
 
-  public int getDataSize()
+  public final int getDataSize()
   {
     return ab == null ? 0 : ab.length;
   }
@@ -91,7 +91,7 @@ public class MicroCache extends ByteDataWriter
    *
    * @return true if id was found
    */
-  public boolean getAndClear( long id64 )
+  public final boolean getAndClear( long id64 )
   {
     if ( size == 0 )
     {
@@ -130,12 +130,12 @@ public class MicroCache extends ByteDataWriter
     return false;
   }
 
-  protected int startPos( int n )
+  protected final int startPos( int n )
   {
     return n > 0 ? fapos[n - 1] & 0x7fffffff : 0;
   }
 
-  public void collect( int threshold )
+  public final void collect( int threshold )
   {
     if ( delcount > threshold )
     {
@@ -178,7 +178,7 @@ public class MicroCache extends ByteDataWriter
     }
   }
 
-  public void unGhost()
+  public final void unGhost()
   {
     ghost = false;
     delcount = 0;
@@ -192,7 +192,7 @@ public class MicroCache extends ByteDataWriter
   /**
    * @return the 64-bit global id for the given cache-position
    */
-  public long getIdForIndex( int i )
+  public final long getIdForIndex( int i )
   {
     int id32 = faid[i];
     return expandId( id32 );
diff --git a/brouter-mapaccess/src/main/java/btools/mapaccess/OsmNodesMap.java b/brouter-mapaccess/src/main/java/btools/mapaccess/OsmNodesMap.java
index 165d729..c62a7f5 100644
--- a/brouter-mapaccess/src/main/java/btools/mapaccess/OsmNodesMap.java
+++ b/brouter-mapaccess/src/main/java/btools/mapaccess/OsmNodesMap.java
@@ -11,7 +11,7 @@ import btools.util.ByteArrayUnifier;
 
 public final class OsmNodesMap
 {
-  private HashMap<OsmNode,OsmNode> hmap = new HashMap<OsmNode,OsmNode>();
+  private HashMap<OsmNode,OsmNode> hmap = new HashMap<OsmNode,OsmNode>(4096);
   
   private ByteArrayUnifier abUnifier = new ByteArrayUnifier( 16384, false );
 
diff --git a/brouter-util/src/main/java/btools/util/ByteDataReader.java b/brouter-util/src/main/java/btools/util/ByteDataReader.java
index 857a9b2..8209c75 100644
--- a/brouter-util/src/main/java/btools/util/ByteDataReader.java
+++ b/brouter-util/src/main/java/btools/util/ByteDataReader.java
@@ -71,13 +71,13 @@ public class ByteDataReader
    *
    * @return the pointer to the first byte after that section
    */
-  public int getEndPointer()
+  public final int getEndPointer()
   {
     int size = readVarLengthUnsigned();
     return aboffset + size;
   }
 
-  public byte[] readDataUntil( int endPointer )
+  public final byte[] readDataUntil( int endPointer )
   {
     int size = endPointer - aboffset;
     if ( size == 0 )
@@ -89,7 +89,7 @@ public class ByteDataReader
     return data;
   }
 
-  public byte[] readVarBytes()
+  public final byte[] readVarBytes()
   {
     int len = readVarLengthUnsigned();
     if ( len == 0 )
@@ -128,7 +128,7 @@ public class ByteDataReader
 	  aboffset += ta.length;
   }
 
-  public boolean hasMoreData()
+  public final boolean hasMoreData()
   {
     return aboffset < aboffsetEnd;
   }
diff --git a/brouter-util/src/main/java/btools/util/SortedHeap.java b/brouter-util/src/main/java/btools/util/SortedHeap.java
index b633db5..943d340 100644
--- a/brouter-util/src/main/java/btools/util/SortedHeap.java
+++ b/brouter-util/src/main/java/btools/util/SortedHeap.java
@@ -12,6 +12,11 @@ import java.util.Random;
 public final class SortedHeap<V>
 {
   private int[][] al;
+  private int[] lv; // low values
+
+  private int[] nextNonEmpty;
+  private int firstNonEmpty;
+  
   private int[] lp; // the low pointers
 
   private Object[][] vla; // value list array
@@ -29,7 +34,7 @@ public final class SortedHeap<V>
   /**
    * @return the lowest key value, or null if none
    */
-  public V popLowestKeyValue()
+  public V popLowestKeyValue2()
   {
     int minId = 0;
     int minIdx = -1;
@@ -53,14 +58,73 @@ public final class SortedHeap<V>
     if ( minIdx == -1 )
       return null;
 
-    int lp_minIdx = lp[minIdx]++;
-    Object[] vla_minIdx = vla[minIdx];
-    V res = (V) vla_minIdx[lp_minIdx];
-    vla_minIdx[lp_minIdx] = null;
     size--;
-    return res;
+
+    return dropLowest( minIdx );
   }
 
+  public V popLowestKeyValue()
+  {
+    int idx = firstNonEmpty;
+    if ( idx < 0 )
+    {
+      return null;
+    }
+    size--;
+    int minId = lv[idx];
+    int minIdx = idx;
+    for (;;)
+    {
+      idx = nextNonEmpty[idx];
+      if ( idx < 0 )
+      {
+        return dropLowest( minIdx );
+      }
+      if ( lv[idx] < minId )
+      {
+        minId = lv[idx];
+        minIdx = idx;
+      }
+    }
+  }
+
+  private V dropLowest( int idx )
+  {
+    int lp_old = lp[idx]++;
+    int lp_new = lp_old+1;
+    if ( lp_new == 4 << idx )
+    {
+      unlinkIdx( idx );
+    }
+    else
+    {
+      lv[idx] = al[idx][lp_new];
+    }
+    Object[] vlai = vla[idx];
+    V res = (V) vlai[lp_old];
+    vlai[lp_old] = null;
+    return res;
+  }
+  
+  private void unlinkIdx( int idx )
+  {
+    if ( idx == firstNonEmpty )
+    {
+      firstNonEmpty = nextNonEmpty[idx];
+      return;
+    }
+    int i = firstNonEmpty;
+    for(;;)
+    {
+      if ( nextNonEmpty[i] == idx )
+      {
+        nextNonEmpty[i] = nextNonEmpty[idx];
+        return;
+      }
+      i = nextNonEmpty[i];
+    }
+  }
+    
   /**
    * add a key value pair to the heap
    * 
@@ -89,7 +153,12 @@ public final class SortedHeap<V>
       {
         al0[lp0-1] = key;
         vla0[lp0-1] = value;
-        lp[0]--;
+        lv[0] = al0[--lp[0]];
+        if ( firstNonEmpty != 0 )
+        {
+          nextNonEmpty[0] = firstNonEmpty;
+          firstNonEmpty = 0;
+        }
         return;
       }
       al0[lp0-1] = al0[lp0];
@@ -104,7 +173,6 @@ public final class SortedHeap<V>
     int cnt = 4; // value count up to idx
     int idx = 1;
     int n = 8;
-    int firstNonEmptyIdx = 0;
     int nonEmptyCount = 1;
 
     for ( ;; )
@@ -123,7 +191,7 @@ public final class SortedHeap<V>
       n <<= 1;
     }
 
-    // create it if not existant
+    // create, if not yet
     if ( al[idx] == null )
     {
       al[idx] = new int[n];
@@ -137,59 +205,49 @@ public final class SortedHeap<V>
     // now merge the contents of arrays 0...idx into idx
     while( nonEmptyCount > 1 )
     {
-      int i = firstNonEmptyIdx;
-      int minId = al[i][lp[i]];
-      int minIdx = i;
+      int neIdx = firstNonEmpty;
+      int minIdx = neIdx;
+      int minId = lv[minIdx];
 
-      for ( i++; i <= idx; i++ )
+      for ( int i = 1; i < nonEmptyCount; i++ )
       {
-        if ( 4 << i > lp[i] )
+        neIdx = nextNonEmpty[neIdx];
+        if ( lv[neIdx] < minId )
         {
-          int currentId = al[i][lp[i]];
-          if ( currentId < minId )
-          {
-            minIdx = i;
-            minId = currentId;
-          }
+          minIdx = neIdx;
+          minId = lv[neIdx];
         }
       }
 
       // current minimum found, copy to target array
-      int sp = lp[minIdx]; // source-pointer
       al_t[tp] = minId;      
-      vla_t[tp++] = vla[minIdx][sp];
-      if ( minIdx != idx )
-      {
-        vla[minIdx][sp] = null;
-      }
-      if ( ++lp[minIdx] ==  4 << minIdx )
+      vla_t[tp++] = dropLowest( minIdx );
+
+      if ( lp[minIdx] ==  4 << minIdx )
       {
         nonEmptyCount--;
-        if ( minIdx == firstNonEmptyIdx )
-        {
-          while( lp[firstNonEmptyIdx] == 4 << firstNonEmptyIdx )
-          {
-            firstNonEmptyIdx++;
-          }
-        }
       }
     }
 
     // only one non-empty index left, so just copy the remaining entries
-    if ( firstNonEmptyIdx != idx ) // no self-copy needed
+    if ( firstNonEmpty != idx ) // no self-copy needed
     {
-      int[] al_s = al[firstNonEmptyIdx];
-      Object[] vla_s = vla[firstNonEmptyIdx];
-      int sp = lp[firstNonEmptyIdx]; // source-pointer      
-      while( sp < 4 << firstNonEmptyIdx )
+      int[] al_s = al[firstNonEmpty];
+      Object[] vla_s = vla[firstNonEmpty];
+      int sp = lp[firstNonEmpty]; // source-pointer      
+      while( sp < 4 << firstNonEmpty )
       {
         al_t[tp] = al_s[sp];     
         vla_t[tp++] = vla_s[sp];
         vla_s[sp++] = null;
       }
-      lp[firstNonEmptyIdx] = sp;
+      lp[firstNonEmpty] = sp;
     }
+    unlinkIdx( firstNonEmpty );
     lp[idx] = n-cnt; // new target low pointer
+    lv[idx] = al[idx][lp[idx]];
+    nextNonEmpty[idx] = firstNonEmpty;
+    firstNonEmpty = idx;
   }
 
   public void clear()
@@ -209,11 +267,17 @@ public final class SortedHeap<V>
       vla = new Object[MAXLISTS][];
       vla[0] = new Object[4];
 
+      lv = new int[MAXLISTS];
+      nextNonEmpty = new int[MAXLISTS];
+
+      firstNonEmpty = -1;
+
       int n = 4;
       for ( int idx = 0; idx < MAXLISTS; idx++ )
       {
         lp[idx] = n;
         n <<= 1;
+        nextNonEmpty[idx] = -1; // no next
       }
     }
   }
@@ -248,7 +312,7 @@ public final class SortedHeap<V>
   {
     SortedHeap<String> sh = new SortedHeap<String>();
     Random rnd = new Random();
-    for( int i = 0; i< 6; i++ )
+    for( int i = 0; i< 100; i++ )
     {
       int val = rnd.nextInt( 1000000 );
       sh.add( val, "" + val );