Whether the performance is sufficient to run smoothly on a 2-core 2GB memory cloud server mainly depends on the specific applications and workloads you are running. Such a configuration is usually suitable for some lightweight applications and tasks, such as personal websites, blogs, small databases, development and testing environments, etc.

　　The following are some common application scenarios:

　　Static website or blog:

　　For a simple static website or blog, a configuration of 2 cores and 2GB of memory is usually sufficient.

　　Small database:

　　For small databases, such as lightweight applications or test databases, this configuration may be sufficient. But for larger or high-traffic databases, more memory may be required.

　　Development and testing environment:

　　If you are doing development and testing, this configuration may be enough to support some small development and testing tasks.

　　​Lightweight application:

　　Some lightweight applications, such as collaboration tools, lightweight CRM systems, etc., may run well under this configuration.

　　But it should be noted that if your application or workload is more complex, requires higher performance, or has a large number of concurrent users, then this configuration may appear limited, causing the server to become laggy.

　　When choosing a server configuration, it's best to evaluate it based on your specific application needs and expected user load. If possible, the configuration can be flexibly adjusted on the cloud service provider's platform to meet actual needs. Different cloud service providers also provide hardware with different performance, so you can consider choosing the appropriate cloud server type based on your specific needs.