added setting to disable tree fix

cookbook/apps.py

@@ -17,6 +17,7 @@ class CookbookConfig(AppConfig):
                                                        'django.db.backends.postgresql']:
             import cookbook.signals  # noqa
 
+        if not settings.DISABLE_TREE_FIX_STARTUP:
             # when starting up run fix_tree to:
             #   a) make sure that nodes are sorted when switching between sort modes
             #   b) fix problems, if any, with tree consistency

recipes/settings.py

@@ -151,6 +151,7 @@ MIDDLEWARE = [
 ]
 
 SORT_TREE_BY_NAME = bool(int(os.getenv('SORT_TREE_BY_NAME', False)))
+DISABLE_TREE_FIX_STARTUP = bool(int(os.getenv('DISABLE_TREE_FIX_STARTUP', False)))
 
 if bool(int(os.getenv('SQL_DEBUG', False))):
     MIDDLEWARE += ('recipes.middleware.SqlPrintingMiddleware',)