Support cross-source dependencies
Additional tests and docs in later patches.
Change-Id: I3b86a1e3dd507fa5e584680fb6c86d35f9ff3e23
Story: 2001334
Task: 5885
diff --git a/doc/source/admin/drivers/zuul.rst b/doc/source/admin/drivers/zuul.rst
index d95dffc..41535ee 100644
--- a/doc/source/admin/drivers/zuul.rst
+++ b/doc/source/admin/drivers/zuul.rst
@@ -26,6 +26,12 @@
When Zuul merges a change to a project, it generates this
event for every open change in the project.
+ .. warning::
+
+ Triggering on this event can cause poor performance when
+ using the GitHub driver with a large number of
+ installations.
+
.. value:: parent-change-enqueued
When Zuul enqueues a change into any pipeline, it generates