Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/Node.java
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/Node.java	(revision 1498330)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/Node.java	(working copy)
@@ -115,29 +115,22 @@
      * A list of children for a node.
      */
     static class Children {
-        
-        final String path;
-        final Revision rev;
+
         final ArrayList<String> children = new ArrayList<String>();
         boolean hasMore;
         long offset;
-        
-        Children(String path, Revision rev) {
-            this.path = path;
-            this.rev = rev;
-        }
 
         public int getMemory() {
-            int size = 200 + path.length() * 2;
+            int size = 200;
             for (String c : children) {
                 size += c.length() * 2 + 40;
             }
             return size;
         }
-        
+
         @Override
         public String toString() {
-            return path + ": " + children.toString();
+            return children.toString();
         }
         
     }
Index: oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/MongoMK.java
===================================================================
--- oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/MongoMK.java	(revision 1498330)
+++ oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/MongoMK.java	(working copy)
@@ -631,7 +631,7 @@
         String to = Utils.getKeyUpperLimit(path);
         List<Map<String, Object>> list = store.query(DocumentStore.Collection.NODES, 
                 from, to, limit);
-        Children c = new Children(path, rev);
+        Children c = new Children();
         Set<Revision> validRevisions = new HashSet<Revision>();
         if (list.size() >= limit) {
             c.hasMore = true;
@@ -841,7 +841,7 @@
         fromChildren = getChildren(path, fromRev, max);
         toChildren = getChildren(path, toRev, max);
         if (!fromChildren.hasMore && !toChildren.hasMore) {
-            diffFewChildren(w, fromChildren, toChildren);
+            diffFewChildren(w, fromChildren, fromRev, toChildren, toRev);
         } else {
             if (FAST_DIFF) {
                 diffManyChildren(w, path, fromRev, toRev);
@@ -849,7 +849,7 @@
                 max = Integer.MAX_VALUE;
                 fromChildren = getChildren(path, fromRev, max);
                 toChildren = getChildren(path, toRev, max);
-                diffFewChildren(w, fromChildren, toChildren);
+                diffFewChildren(w, fromChildren, fromRev, toChildren, toRev);
             }
         }
         return w.toString();
@@ -891,14 +891,14 @@
         }
     }
     
-    private void diffFewChildren(JsopWriter w, Children fromChildren, Children toChildren) {
+    private void diffFewChildren(JsopWriter w, Children fromChildren, Revision fromRev, Children toChildren, Revision toRev) {
         Set<String> childrenSet = new HashSet<String>(toChildren.children);
         for (String n : fromChildren.children) {
             if (!childrenSet.contains(n)) {
                 w.tag('-').value(n).newline();
             } else {
-                Node n1 = getNode(n, fromChildren.rev);
-                Node n2 = getNode(n, toChildren.rev);
+                Node n1 = getNode(n, fromRev);
+                Node n2 = getNode(n, toRev);
                 // this is not fully correct:
                 // a change is detected if the node changed recently,
                 // even if the revisions are well in the past
@@ -1520,7 +1520,7 @@
         Children c = nodeChildrenCache.getIfPresent(path + "@" + rev);
         if (isNew || (!isDelete && c != null)) {
             String key = path + "@" + rev;
-            Children c2 = new Children(path, rev);
+            Children c2 = new Children();
             TreeSet<String> set = new TreeSet<String>();
             if (c != null) {
                 set.addAll(c.children);
Index: oak-core/src/test/java/org/apache/jackrabbit/oak/plugins/mongomk/MeasureMemory.java
===================================================================
--- oak-core/src/test/java/org/apache/jackrabbit/oak/plugins/mongomk/MeasureMemory.java	(revision 1498330)
+++ oak-core/src/test/java/org/apache/jackrabbit/oak/plugins/mongomk/MeasureMemory.java	(working copy)
@@ -157,7 +157,7 @@
     }
 
     static Children generateNodeChild(int childCount) {
-        Children n = new Children(new String("_id"), new Revision(1, 2, 3));
+        Children n = new Children();
         for (int i = 0; i < childCount; i++) {
             n.children.add("child" + i);
         }