More conservative connection pooling

Author: mistercrunch

airflow/settings.py

@@ -29,7 +29,7 @@
 engine_args = {}
 if 'sqlite' not in SQL_ALCHEMY_CONN:
     # Engine args not supported by sqlite
-    engine_args['pool_size'] = 25
+    engine_args['pool_size'] = 5
     engine_args['pool_recycle'] = 3600
 
 engine = create_engine(SQL_ALCHEMY_CONN, **engine_args)