diff -r c0a1686d9391 -r 4369c00a8ee1 contrib/perf.py
--- a/contrib/perf.py	Mon Nov 19 23:14:46 2018 +0000
+++ b/contrib/perf.py	Tue Nov 20 10:10:25 2018 +0000
@@ -537,14 +537,15 @@
     timer, fm = gettimer(ui, opts)
     svfs = getsvfs(repo)
     repocleartagscache = repocleartagscachefunc(repo)
-    def t():
+    def s():
         repo.changelog = mercurial.changelog.changelog(svfs)
         rootmanifest = mercurial.manifest.manifestrevlog(svfs)
         repo.manifestlog = mercurial.manifest.manifestlog(svfs, repo,
                                                           rootmanifest)
         repocleartagscache()
+    def t():
         return len(repo.tags())
-    timer(t)
+    timer(t, setup=s)
     fm.end()
 
 @command(b'perfancestors', formatteropts)