In recent years, several technologies were developed enabling the automated provisioning and decommissioning of cloud applications. To reduce costs, these applications can be terminated and restarted on demand. However, as an application is terminated, its current application state, i.e., all application specific data is deleted along with the running application instance. This application state may be holding all business-critical information, and, hence, must be saved before the application is terminated. One possibility to save application states is to create VM snapshots although this is not always possible or sufficient. Therefore, we introduce two approaches: (1) a concept to generically terminate applications and save their internal state, and (2) an approach to reinstate the application in the same state again. To evaluate their practical feasibility, we implemented a proof of concept in the OpenTOSCA ecosystem.

中文翻译：

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冻结和解冻云应用程序：自动保存和还原正在运行的应用程序

近年来，开发了多种技术，可实现对云应用程序的自动配置和停用。为了降低成本，可以根据需要终止和重新启动这些应用程序。但是，随着应用程序终止，其当前应用程序状态（即所有特定于应用程序的数据）与正在运行的应用程序实例一起被删除。此应用程序状态可能包含所有关键业务信息，因此必须在终止应用程序之前保存该状态。保存应用程序状态的一种可能性是创建VM快照，尽管这并不总是可能或足够的。因此，我们引入两种方法：（1）一种一般终止应用程序并保存其内部状态的概念，以及（2）一种将应用程序再次恢复为相同状态的方法。