remotefilelog: disable descendantrevfastpath by default

Summary:
With treemanifest and the eden api, descendantrevfastpath (which downloads all
the manifests) is slower than just downloading the history from the eden api.

We still want to record the descendantrev if we already know the real linkrev
of the current filenode, as that will still be fast.

Reviewed By: quark-zju

Differential Revision: D15943076

fbshipit-source-id: c6013801822bdfa3196e60cbcd34a9ce184c5c5f

edenscm/hgext/remotefilelog/__init__.py

@@ -246,6 +246,7 @@ command = registrar.command(cmdtable)
 configtable = {}
 configitem = registrar.configitem(configtable)
 
+configitem("remotefilelog", "descendantrevfastpath", default=False)
 configitem("remotefilelog", "fetchpacks", default=False)
 configitem("remotefilelog", "localdatarepack", default=False)
 configitem("remotefilelog", "packlocaldata", default=False)

edenscm/hgext/remotefilelog/remotefilectx.py

@@ -71,7 +71,7 @@ class remotefilectx(context.filectx):
         )
         self._ancestormap = ancestormap
         self._descendantrevfastpath = repo.ui.configbool(
-            "remotefilelog", "descendantrevfastpath", True
+            "remotefilelog", "descendantrevfastpath"
         )
 
     def size(self):
@@ -215,7 +215,7 @@ class remotefilectx(context.filectx):
             p1ctx = remotefilectx(
                 repo, path, fileid=p1, filelog=flog, ancestormap=ancestormap
             )
-            if self._descendantrevfastpath:
+            if self._descendantrevfastpath or "_changeid" in self.__dict__:
                 p1ctx._descendantrev = self.rev()
             results.append(p1ctx)
 
@@ -225,7 +225,7 @@ class remotefilectx(context.filectx):
             p2ctx = remotefilectx(
                 repo, path, fileid=p2, filelog=flog, ancestormap=ancestormap
             )
-            if self._descendantrevfastpath:
+            if self._descendantrevfastpath or "_changeid" in self.__dict__:
                 p2ctx._descendantrev = self.rev()
             results.append(p2ctx)
 
@@ -589,7 +589,7 @@ class remoteworkingfilectx(context.workingfilectx, remotefilectx):
     def __init__(self, repo, path, filelog=None, workingctx=None):
         self._ancestormap = None
         self._descendantrevfastpath = repo.ui.configbool(
-            "remotefilelog", "descendantrevfastpath", True
+            "remotefilelog", "descendantrevfastpath"
         )
         return super(remoteworkingfilectx, self).__init__(
             repo, path, filelog, workingctx

tests/test-fb-hgext-treemanifest-treeonly-copyamend.t

@@ -117,10 +117,10 @@ Rename the file in a commit
   11 trees fetched over *s (glob)
   * files fetched over *s (glob)
 
-Amend the commit to add a new file with an empty cache
+Amend the commit to add a new file with an empty cache, with descendantrevfastpath enabled
   $ clearcache
   $ echo more >> a/b/c/d/e/f/g/h/i/j/file3
-  $ hg amend -A --config remotefilelog.debug=True
+  $ hg amend -A --config remotefilelog.debug=True --config remotefilelog.descendantrevfastpath=True
   adding a/b/c/d/e/f/g/h/i/j/file3
   fetching tree '' efa8fa4352b919302f90e85924e691a632d6bea0, found via 9f95b8f1011f
   11 trees fetched over *s (glob)