I. Reliability Assurance of Cloud Computing The reliability of cloud computing refers to the fact that its system will not fail or be interrupted during a long period of operation, thus ensuring the integrity and availability of user data and services. In order to improve the reliability of cloud computing, the following measures need to be taken: 1. Data Backup and Recovery In cloud computing, data backup and recovery is the key to ensure data integrity and availability. When cloud computing fails, data needs to be backed up in a timely manner so that it can be quickly recovered in the event of a failure. It is also necessary to formulate a backup strategy, which is based on factors such as business requirements and data types.2. Highly Available Architecture Design Highly available architecture design is one of the most important means to ensure the reliability of cloud computing. By using technologies such as load balancing, fault tolerance and failover, it is possible to automatically switch to the standby node when the cloud computing platform fails to ensure the continuity of the system service.3. Disaster tolerance backupDisaster tolerance backup is a technical means of preventing security accidents and improving the reliability of the system, and it ensures that the cloud computing can be quickly switched over to the cloud computing system in the face of natural disasters, man-made damage, etc., through the setup of standby data centers, multi-live data centers, or off-site redundancy. By setting up multiple live data centers or off-site redundancy, it ensures that cloud computing can be quickly switched to standby nodes in the face of natural disasters, human damage, etc., so as to ensure service continuity. The performance of cloud computing refers to the fact that the system can keep running efficiently for a long period of time so as to meet the needs of users. In order to improve the performance of cloud computing, the following measures need to be taken: 1. Hardware Optimization Hardware optimization is the basis for improving the performance of cloud computing. By increasing hardware resources such as CPU, memory, disk and network bandwidth, the performance of cloud computing platform can be effectively improved. At the same time, it is also necessary to reasonably allocate hardware resources according to factors such as business requirements and server load.2. Software optimization Software optimization is the key to improving the performance of cloud computing. By optimizing the design and implementation of key modules such as database, cache, scheduling, etc., the performance of cloud computing platform can be effectively improved. At the same time, it is also necessary to select the appropriate software architecture and technology based on factors such as business requirements and data types.3. Resource PoolingResource pooling is a way of managing cloud computing platforms, in which different types of resources can be managed in a unified way, and they can be quickly provisioned and applied. Through resource pooling, resource utilization can be maximized, thus improving the performance of the cloud computing platform. To summarize the reliability and performance guarantee of cloud computing is a key element to ensure the successful application of cloud computing. The reliability and performance of cloud computing platform can be effectively improved by taking measures such as data backup and recovery, high availability architecture design, disaster recovery, hardware optimization, software optimization and resource pooling. In actual application, it is also necessary to monitor and improve in a timely manner according to business requirements and user feedback, so as to continuously improve the reliability and performance of cloud computing.