# HG changeset patch
# User Benoit Boissinot <benoit.boissinot@ens-lyon.org>
# Date 1140657428 -3600
# Node ID 98b6c1cad58b6f92b045c015095c14ff66d9e1cd
# Parent  83c6d83559099eaa3886c9fca5e36a78fee9fb9a
only write the dirstate when something changed


diff --git a/mercurial/dirstate.py b/mercurial/dirstate.py
--- a/mercurial/dirstate.py
+++ b/mercurial/dirstate.py
@@ -213,6 +213,8 @@ class dirstate(object):
         self.markdirty()
 
     def write(self):
+        if not self.dirty:
+            return
         st = self.opener("dirstate", "w", atomic=True)
         st.write("".join(self.pl))
         for f, e in self.map.items():