diff -r e1b32dc4646c -r 2f626233859b mercurial/setdiscovery.py
--- a/mercurial/setdiscovery.py	Fri Apr 13 10:51:23 2018 -0700
+++ b/mercurial/setdiscovery.py	Fri Apr 13 11:02:34 2018 -0700
@@ -155,11 +155,14 @@
     sample = _limitsample(ownheads, initialsamplesize)
     # indices between sample and externalized version must match
     sample = list(sample)
-    batch = remote.iterbatch()
-    batch.heads()
-    batch.known(dag.externalizeall(sample))
-    batch.submit()
-    srvheadhashes, yesno = batch.results()
+
+    with remote.commandexecutor() as e:
+        fheads = e.callcommand('heads', {})
+        fknown = e.callcommand('known', {
+            'nodes': dag.externalizeall(sample),
+        })
+
+    srvheadhashes, yesno = fheads.result(), fknown.result()
 
     if cl.tip() == nullid:
         if srvheadhashes != [nullid]: