diff --git a/swh/objstorage/api/client.py b/swh/objstorage/api/client.py
--- a/swh/objstorage/api/client.py
+++ b/swh/objstorage/api/client.py
@@ -8,6 +8,8 @@
 from swh.objstorage.exc import Error, ObjNotFoundError, ObjStorageAPIError
 from swh.objstorage.objstorage import DEFAULT_CHUNK_SIZE, DEFAULT_LIMIT
 
+SHA1_SIZE = 20
+
 
 class RemoteObjStorage:
     """Proxy to a remote object storage.
@@ -80,10 +82,12 @@
         )
 
     def __iter__(self):
-        yield from self._proxy.get_stream("content")
+        yield from self.list_content()
 
     def list_content(self, last_obj_id=None, limit=DEFAULT_LIMIT):
         params = {"limit": limit}
         if last_obj_id:
             params["last_obj_id"] = hashutil.hash_to_hex(last_obj_id)
-        yield from self._proxy.get_stream("content", params=params)
+        yield from self._proxy.get_stream(
+            "content", chunk_size=SHA1_SIZE, params=params
+        )