diff --git a/mercurial/exchange.py b/mercurial/exchange.py
--- a/mercurial/exchange.py
+++ b/mercurial/exchange.py
@@ -297,7 +297,11 @@ def _pushdiscoveryobsmarkers(pushop):
     if (obsolete._enabled
         and pushop.repo.obsstore
         and 'obsolete' in pushop.remote.listkeys('namespaces')):
-        pushop.outobsmarkers = pushop.repo.obsstore
+        repo = pushop.repo
+        # very naive computation, that can be quite expensive on big repo.
+        # However: evolution is currently slow on them anyway.
+        nodes = (c.node() for c in repo.set('::%ln', pushop.futureheads))
+        pushop.outobsmarkers = pushop.repo.obsstore.relevantmarkers(nodes)
 
 @pushdiscovery('bookmarks')
 def _pushdiscoverybookmarks(pushop):
@@ -680,7 +684,7 @@ def _pushobsolete(pushop):
     repo = pushop.repo
     remote = pushop.remote
     pushop.stepsdone.add('obsmarkers')
-    if (pushop.outobsmarkers):
+    if pushop.outobsmarkers:
         rslts = []
         remotedata = obsolete._pushkeyescape(pushop.outobsmarkers)
         for key in sorted(remotedata, reverse=True):
diff --git a/tests/test-bundle2.t b/tests/test-bundle2.t
--- a/tests/test-bundle2.t
+++ b/tests/test-bundle2.t
@@ -878,7 +878,7 @@ push
   remote: adding manifests
   remote: adding file changes
   remote: added 1 changesets with 0 changes to 0 files (-1 heads)
-  remote: 5 new obsolescence markers
+  remote: 1 new obsolescence markers
   updating bookmark book_eea1
   exporting bookmark book_eea1
   $ hg -R other log -G
@@ -894,10 +894,6 @@ push
   1111111111111111111111111111111111111111 9520eea781bcca16c1e15acc0ba14335a0e8e5ba 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
   2222222222222222222222222222222222222222 24b6387c8c8cae37178880f3fa95ded3cb1cf785 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
   3333333333333333333333333333333333333333 eea13746799a9e0bfd88f29d3c2e9dc9389f524f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
-  4444444444444444444444444444444444444444 02de42196ebee42ef284b6780a87cdc96e8eaab6 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
-  5555555555555555555555555555555555555555 42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
-  6666666666666666666666666666666666666666 5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
-  7777777777777777777777777777777777777777 32af7686d403cf45b5d95f2d70cebea587ac806a 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
 
 pull over ssh