关键词: 持续数据保护, 日志盘分区, 元数据, B 树, 索引, 虚拟磁盘

Abstract: In the traditional blocklevel continuous data protection (CDP) system, once the recovery task at a certain point in time has been completed, the data state of the protected disk at the current time is completely covered. The current work can continue which means that the protected disk must be restored to the latest state again. Aiming at the problem of “oneview, tworecovery” of the traditional CDP system recovery function, a log disk partitioning technology and a metadata hierarchical multilevel indexing technology are proposed. The metadata and the changed data are respectively stored in different areas of the log disk, and the metadata block and the variable data block are organized by using the B+ tree and the improved B+ tree to form a hierarchical multilevel index of the metadata, and any point in the past will be used. The data is mounted to a virtual disk for user viewing. It has been proved by experiments that the method provides users with data at any point in time without affecting the current data state of the protected disk, which simplifies operations of users and reduces their time consumption.

Key words: continuous data protection (CDP), log disk partition, metadata, B tree, index, virtual disk