changeset 25221:eafa06e9edde

treemanifest: speed up commit using dirty flag We currently avoid saving a treemanifest revision if it's the same as one of it's parents. This is checked by comparing the generated text for all three versions. Let's avoid that when possible by comparing the nodeids for clean (not dirty) nodes. On the Mozilla repo, this speeds up commit from 2.836s to 2.343s.
author Martin von Zweigbergk <martinvonz@google.com>
date Mon, 18 May 2015 21:31:40 -0700
parents f0fbd88b21fb
children 0de132d5328a
files mercurial/manifest.py
diffstat 1 files changed, 8 insertions(+), 2 deletions(-) [+]
line wrap: on
line diff
--- a/mercurial/manifest.py	Thu Feb 26 08:16:13 2015 -0800
+++ b/mercurial/manifest.py	Mon May 18 21:31:40 2015 -0700
@@ -759,6 +759,9 @@
         _diff(self, m2)
         return result
 
+    def unmodifiedsince(self, m2):
+        return not self._dirty and not m2._dirty and self._node == m2._node
+
     def parse(self, text, readsubtree):
         for f, n, fl in _parse(text):
             if fl == 'd':
@@ -951,13 +954,16 @@
         return n
 
     def _addtree(self, m, transaction, link, m1, m2):
+        # If the manifest is unchanged compared to one parent,
+        # don't write a new revision
+        if m.unmodifiedsince(m1) or m.unmodifiedsince(m2):
+            return m.node()
         def writesubtree(subm, subp1, subp2):
             sublog = self.dirlog(subm.dir())
             sublog.add(subm, transaction, link, subp1, subp2, None, None)
         m.writesubtrees(m1, m2, writesubtree)
         text = m.dirtext(self._usemanifestv2)
-        # If the manifest is unchanged compared to one parent,
-        # don't write a new revision
+        # Double-check whether contents are unchanged to one parent
         if text == m1.dirtext(self._usemanifestv2):
             n = m1.node()
         elif text == m2.dirtext(self._usemanifestv2):