--- a/mercurial/revlog.py	Fri Jan 15 01:58:59 2021 +0100
+++ b/mercurial/revlog.py	Wed Jan 20 14:47:13 2021 +0100
@@ -2375,6 +2375,7 @@
         deltas,
         linkmapper,
         transaction,
+        alwayscache=False,
         addrevisioncb=None,
         duplicaterevisioncb=None,
     ):
@@ -2475,7 +2476,7 @@
                     (baserev, delta),
                     ifh,
                     dfh,
-                    alwayscache=bool(addrevisioncb),
+                    alwayscache=alwayscache,
                     deltacomputer=deltacomputer,
                 )