diff --git a/source/net/yacy/kelondro/blob/Heap.java b/source/net/yacy/kelondro/blob/Heap.java
index e1b32405c..49252f29f 100755
--- a/source/net/yacy/kelondro/blob/Heap.java
+++ b/source/net/yacy/kelondro/blob/Heap.java
@@ -281,6 +281,10 @@ public final class Heap extends HeapModifier implements BLOB {
     public void finalize() {
         this.close();
     }
+    
+    public int getBuffermax() {
+        return this.buffermax;
+    }
 
     /**
      * write a whole byte array as BLOB to the table
diff --git a/source/net/yacy/kelondro/blob/HeapReader.java b/source/net/yacy/kelondro/blob/HeapReader.java
index e0f70864d..dbaeb5394 100644
--- a/source/net/yacy/kelondro/blob/HeapReader.java
+++ b/source/net/yacy/kelondro/blob/HeapReader.java
@@ -256,6 +256,10 @@ public class HeapReader {
         return this.heapFile.getName();
     }
     
+    public File location() {
+        return this.heapFile;
+    }
+    
     /**
      * the number of BLOBs in the heap
      * @return the number of BLOBs in the heap
@@ -491,14 +495,14 @@ public class HeapReader {
      * this is used to import heap dumps into a write-enabled index heap
      */
     public static class entries implements
-        CloneableIterator<Map.Entry<String, byte[]>>,
-        Iterator<Map.Entry<String, byte[]>>,
-        Iterable<Map.Entry<String, byte[]>> {
+        CloneableIterator<Map.Entry<byte[], byte[]>>,
+        Iterator<Map.Entry<byte[], byte[]>>,
+        Iterable<Map.Entry<byte[], byte[]>> {
         
         DataInputStream is;
         int keylen;
         private final File blobFile;
-        Map.Entry<String, byte[]> nextEntry;
+        Map.Entry<byte[], byte[]> nextEntry;
         
         public entries(final File blobFile, final int keylen) throws IOException {
             if (!(blobFile.exists())) throw new IOException("file " + blobFile + " does not exist");
@@ -508,7 +512,7 @@ public class HeapReader {
             this.nextEntry = next0();
         }
 
-        public CloneableIterator<Entry<String, byte[]>> clone(Object modifier) {
+        public CloneableIterator<Entry<byte[], byte[]>> clone(Object modifier) {
             // if the entries iterator is cloned, close the file!
             if (is != null) try { is.close(); } catch (final IOException e) {}
             is = null;
@@ -527,7 +531,7 @@ public class HeapReader {
             return false;
         }
 
-        private Map.Entry<String, byte[]> next0() {
+        private Map.Entry<byte[], byte[]> next0() {
             try {
                 while (true) {
                     int len = is.readInt();
@@ -536,15 +540,15 @@ public class HeapReader {
                     byte[] payload = new byte[len - this.keylen];
                     if (is.read(payload) < payload.length) return null;
                     if (key[0] == 0) continue; // this is an empty gap
-                    return new entry(new String(key), payload);
+                    return new entry(key, payload);
                 }
             } catch (final IOException e) {
                 return null;
             }
         }
         
-        public Map.Entry<String, byte[]> next() {
-            final Map.Entry<String, byte[]> n = this.nextEntry;
+        public Map.Entry<byte[], byte[]> next() {
+            final Map.Entry<byte[], byte[]> n = this.nextEntry;
             this.nextEntry = next0();
             return n;
         }
@@ -553,7 +557,7 @@ public class HeapReader {
             throw new UnsupportedOperationException("blobs cannot be altered during read-only iteration");
         }
 
-        public Iterator<Map.Entry<String, byte[]>> iterator() {
+        public Iterator<Map.Entry<byte[], byte[]>> iterator() {
             return this;
         }
         
@@ -568,16 +572,16 @@ public class HeapReader {
         }
     }
 
-    public static class entry implements Map.Entry<String, byte[]> {
-        private final String s;
+    public static class entry implements Map.Entry<byte[], byte[]> {
+        private final byte[] s;
         private byte[] b;
         
-        public entry(final String s, final byte[] b) {
+        public entry(final byte[] s, final byte[] b) {
             this.s = s;
             this.b = b;
         }
     
-        public String getKey() {
+        public byte[] getKey() {
             return s;
         }
 
diff --git a/source/net/yacy/kelondro/blob/HeapWriter.java b/source/net/yacy/kelondro/blob/HeapWriter.java
index 30e01844f..df3b014b8 100644
--- a/source/net/yacy/kelondro/blob/HeapWriter.java
+++ b/source/net/yacy/kelondro/blob/HeapWriter.java
@@ -38,7 +38,7 @@ import net.yacy.kelondro.order.Digest;
 import net.yacy.kelondro.util.FileUtils;
 
 
-public final class HeapWriter  {
+public final class HeapWriter {
 
     private final int          keylength;     // the length of the primary key
     private HandleMap          index;         // key/seek relation for used records
diff --git a/source/net/yacy/kelondro/rwi/ReferenceContainerArray.java b/source/net/yacy/kelondro/rwi/ReferenceContainerArray.java
index 3464890c3..605375d96 100644
--- a/source/net/yacy/kelondro/rwi/ReferenceContainerArray.java
+++ b/source/net/yacy/kelondro/rwi/ReferenceContainerArray.java
@@ -310,7 +310,7 @@ public final class ReferenceContainerArray<ReferenceType extends Reference> {
             donesomething = true;
         }
 
-        // merge very old files with it self (hack from sixcooler, see http://forum.yacy-websuche.de/viewtopic.php?p=15004#p15004)
+        // rewrite old files (hack from sixcooler, see http://forum.yacy-websuche.de/viewtopic.php?p=15004#p15004)
         while (this.merger.queueLength() < 1) {
             File ff = this.array.unmountOldest();
             if (ff == null) break;
diff --git a/source/net/yacy/kelondro/rwi/ReferenceIterator.java b/source/net/yacy/kelondro/rwi/ReferenceIterator.java
index 47d755c43..60878d15a 100644
--- a/source/net/yacy/kelondro/rwi/ReferenceIterator.java
+++ b/source/net/yacy/kelondro/rwi/ReferenceIterator.java
@@ -65,9 +65,9 @@ public class ReferenceIterator <ReferenceType extends Reference> implements Clon
      * because they may get very large, it is wise to deallocate some memory before calling next()
      */
     public ReferenceContainer<ReferenceType> next() {
-        Map.Entry<String, byte[]> entry = blobs.next();
+        Map.Entry<byte[], byte[]> entry = blobs.next();
         byte[] payload = entry.getValue();
-        return new ReferenceContainer<ReferenceType>(factory, entry.getKey().getBytes(), RowSet.importRowSet(payload, payloadrow));
+        return new ReferenceContainer<ReferenceType>(factory, entry.getKey(), RowSet.importRowSet(payload, payloadrow));
     }
     
     public void remove() {