diff -r bb6936bec727 -r 7187f6e923d5 mercurial/hgweb/hgweb_mod.py
--- a/mercurial/hgweb/hgweb_mod.py	Wed Sep 02 16:07:35 2015 -0400
+++ b/mercurial/hgweb/hgweb_mod.py	Thu Sep 03 18:32:17 2015 -0500
@@ -201,11 +201,13 @@
 
     def refresh(self):
         repostate = []
+        mtime = 0
         # file of interrests mtime and size
         for meth, fname in foi:
             prefix = getattr(self.repo, meth)
             st = get_stat(prefix, fname)
             repostate.append((st.st_mtime, st.st_size))
+            mtime = max(mtime, st.st_mtime)
         repostate = tuple(repostate)
         # we need to compare file size in addition to mtime to catch
         # changes made less than a second ago
@@ -215,7 +217,7 @@
             # update these last to avoid threads seeing empty settings
             self.repostate = repostate
             # mtime is needed for ETag
-            self.mtime = st.st_mtime
+            self.mtime = mtime
 
     def run(self):
         """Start a server from CGI environment.