Index: src/main/java/org/apache/jackrabbit/oak/plugins/backup/FileStoreBackup.java
===================================================================
--- src/main/java/org/apache/jackrabbit/oak/plugins/backup/FileStoreBackup.java	(revision 1656785)
+++ src/main/java/org/apache/jackrabbit/oak/plugins/backup/FileStoreBackup.java	(working copy)
@@ -68,16 +68,16 @@
                 before = EMPTY_NODE;
             } else {
                 // 3.2 try to retrieve the previously backed up checkpoint
-                before = store.retrieve(beforeCheckpoint);
-                if (before == null) {
+//                before = store.retrieve(beforeCheckpoint);
+//                if (before == null) {
                     // the previous checkpoint is no longer available,
                     // so use the backed up state as the basis of the
                     // incremental backup diff
                     before = state.getChildNode("root");
-                }
+//                }
             }
 
-            Compactor compactor = new Compactor(backup.getTracker().getWriter());
+            Compactor compactor = new Compactor(backup.getTracker().getWriter(), true);
             SegmentNodeState after = compactor.compact(before, current);
 
             // 4. commit the backup