--- src/sys/vfs/hammer/Attic/hammer.txt	2007/10/12 17:17:20	1.2
+++ src/sys/vfs/hammer/Attic/hammer.txt	2007/11/07 00:43:24	1.3
@@ -81,10 +81,14 @@ $DragonFly$
     and deletion transaction id which is indexed along with the key.
 
     HAMMER utilizes a 64 bit key to index all records.  Regular files use
-    the base data offset of the record as the key while directories use a
-    namekey hash as the key and store one directory entry per record.  For
-    all intents and purposes a directory can store an unlimited number of
-    files. 
+    (base_data_offset + data_len) as the key in a data record.  This allows
+    use to use a non-ranged B-Tree search to locate and iterate through
+    data records and also allows us to use variable block sizes for
+    data records without regards to the stored history.
+
+    Directories use a namekey hash as the key and store one directory
+    entry per record.  For all intents and purposes a directory can
+    store an unlimited number of files.
 
     HAMMER is also capable of associating any number of out-of-band
     attributes with a filesystem object using a separate key space.  This