Rev 5789: Include update in What's New for the performance improvements and bug #759096 in http://bazaar.launchpad.net/~jameinel/bzr/2.4-revert-faster-759096

[John Arbash Meinel]

At http://bazaar.launchpad.net/~jameinel/bzr/2.4-revert-faster-759096

------------------------------------------------------------
revno: 5789
revision-id: john at arbash-meinel.com-20110415081656-d3ipmkl0vujwpntl
parent: john at arbash-meinel.com-20110414145910-yovxz9rephqynmmt
fixes bug(s): https://launchpad.net/bugs/759096
committer: John Arbash Meinel <john at arbash-meinel.com>
branch nick: 2.4-revert-faster-759096
timestamp: Fri 2011-04-15 10:16:56 +0200
message:
  Include update in What's New for the performance improvements and bug #759096
-------------- next part --------------
=== modified file 'doc/en/release-notes/bzr-2.4.txt'
--- a/doc/en/release-notes/bzr-2.4.txt	2011-04-11 09:56:15 +0000
+++ b/doc/en/release-notes/bzr-2.4.txt	2011-04-15 08:16:56 +0000
@@ -63,6 +63,12 @@
   this might be required for "installing" extra dependencies for some plugins.
   (Alexander Belchenko, #743256)
 
+* ``transform.revert()`` has been updated to use
+  ``wt.iter_changes(basis_tree)`` rather than
+  ``basis_tree.iter_changes(wt)``. This allows the optimized code path to
+  kick in, improving ``bzr revert`` times significantly (33s to 4s on
+  large trees, 0.7s to 0.3s on small trees.) (John Arbash Meinel, #759096)
+
 * ``TreeTransform.create_file/new_file`` can now take an optional ``sha1``
   parameter. If supplied, when the transform is applied, it will then call
   ``self._tree._observed_sha1`` for those files. This lets us update the

=== modified file 'doc/en/whats-new/whats-new-in-2.4.txt'
--- a/doc/en/whats-new/whats-new-in-2.4.txt	2011-03-15 08:07:04 +0000
+++ b/doc/en/whats-new/whats-new-in-2.4.txt	2011-04-15 08:16:56 +0000
@@ -48,6 +48,23 @@
 format.  Refer to ``bzr help changelog_merge`` for documentation on how to
 enable it and what it can do.
 
+Faster operations on Large Trees
+********************************
+
+Many bzr commands used to run into pathological behavior on large trees
+(>10k files), reading the inventory data random order causing cache
+thrashing. Various other tweaks have been applied with feedback from large
+trees. A possibly incomplete list is as follows for running commands on a
+70k file tree::
+
+    bzr-2.3 bzr-2.4 action
+    3m39s   1m03s   bzr co --lightweight
+      38s      6s   bzr revert
+    4m47s     27s   bzr merge
+    4m58s     32s   bzr up
+    
+
+
 Further information
 *******************