--- a/contrib/perf.py	Tue Jul 31 19:37:48 2018 +0200
+++ b/contrib/perf.py	Tue Jul 31 19:37:54 2018 +0200
@@ -807,7 +807,7 @@
     else:
         t = repo.manifestlog._revlog.lookup(rev)
     def d():
-        repo.manifestlog.clearcaches()
+        repo.manifestlog.clearcaches(clear_persisted_data=clear_disk)
         repo.manifestlog[t].read()
     timer(d)
     fm.end()