diff --git a/hgext3rd/perftweaks.py b/hgext3rd/perftweaks.py
--- a/hgext3rd/perftweaks.py
+++ b/hgext3rd/perftweaks.py
@@ -16,8 +16,10 @@
 
 from mercurial import (
     branchmap,
+    commands,
     dispatch,
     extensions,
+    localrepo,
     merge,
     namespaces,
     phases,
@@ -40,6 +42,7 @@
     wrapfunction(branchmap, 'read', _branchmapread)
     wrapfunction(branchmap, 'replacecache', _branchmapreplacecache)
     wrapfunction(branchmap, 'updatecache', _branchmapupdatecache)
+    wrapfunction(commands, '_docommit', _docommit)
     if ui.configbool('perftweaks', 'preferdeltas'):
         wrapfunction(revlog.revlog, '_isgooddelta', _isgooddelta)
 
@@ -158,6 +161,34 @@
     partial.update(repo, None)
     repo._branchcaches[repo.filtername] = partial
 
+# _docommit accesses "branchheads" just to decide whether to show "(created new
+# head)" or not. Accessing branchheads requires calling "headrevs()" which is
+# expensive since it scans entire changelog. We can just test if "." has any
+# existing children to know if there is a new head or not.
+def _singlebranchheads(orig, repo, branch):
+    unfi = repo.unfiltered()
+    dotrev = unfi['.'].rev()
+    children = None
+    try:
+        children = unfi.changelog.index._children(dotrev)
+    except Exception:
+        pass
+    if (repo.ui.configbool('tweakdefaults', 'allowbranch', True)
+        or children is None):
+        return orig(repo, branch)
+    if children:
+        # dotrev is not a head. Return a faked head so the new rev is not part
+        # of it and "created new head" will be printed.
+        return ['\0' * 20]
+    else:
+        # dotrev is a head. Return a list containing that head.
+        return [repo.changelog.node(dotrev)]
+
+def _docommit(orig, ui, repo, *pats, **opts):
+    with extensions.wrappedfunction(localrepo.localrepository,
+                                    'branchheads', _singlebranchheads):
+        return orig(ui, repo, *pats, **opts)
+
 def _branchmapwrite(orig, self, repo):
     if repo.ui.configbool('perftweaks', 'disablebranchcache'):
         # Since we don't read the branchcache, don't bother writing it.