The system shall, through the flow control mechanism for service requests, control the flow of a small number of transactions with a high degree of impact during the time when the performance of the system fluctuates, so as to ensure the smooth operation of the system. The platform shall implement flow control for the system based on the logical architecture of the system, based on the transaction flow and transaction status at different levels of each sub-system and the determined control strategy and control rules. When there are problems or attacks on external access, etc., flow control is activated and services are downgraded.