Unlike other serverless Platform as a Service (PaaS) products, SAE is not request-triggered. Request-triggered products start instances and charge you only when requests are received. When there are no requests, the instances are scaled to zero, and you are not charged. In contrast, SAE is a serverless PaaS product designed for application hosting. SAE manages the lifecycle of applications and tasks. Billing starts when you create application and task instances, and you are charged for the CPU and memory that your running instances consume. For more information, see Billing overview.