Reduce memory usage on ServiceContainer destruction

The closures in ServiceContainer::$serviceInstantiators are circular
references which prevent destruction of the object. So, delete these
when destroy() is called. Also delete the service instances for good
measure.

Change-Id: Ic8487cb533a09a8fcc69eba4f5d1bbb71558ae08

diff --git a/includes/services/ServiceContainer.php b/includes/services/ServiceContainer.php
index 30f8295..d934d27 100644 (file)
--- a/includes/services/ServiceContainer.php
+++ b/includes/services/ServiceContainer.php
@@ -100,6 +100,12 @@ class ServiceContainer implements DestructibleService {
                        }
                }
 
+               // Break circular references due to the $this reference in closures, by
+               // erasing the instantiator array. This allows the ServiceContainer to
+               // be deleted when it goes out of scope.
+               $this->serviceInstantiators = [];
+               // Also remove the services themselves, to avoid confusion.
+               $this->services = [];
                $this->destroyed = true;
        }