Snapshot method, apparatus and system, and readable storage medium

Abstract

The invention discloses a snapshot method, which comprises the following steps: a snapshot volume is created according to a source volume, and the snapshot volume comprises all initial data blocks ofthe source volume; the new data block is redirected to the previous snapshot volume whenever a data block is modified in the source volume, and an indexing relationship between the new data block andthe modified data block is established; when a new snapshot point arrives, the current snapshot volume is determined based on the last snapshot volume and the indexing relationship. It can be seen that all the initial data blocks and new data blocks of the source volume are stored in the same snapshot volume, so that the data can be recovered to the past time point through each snapshot volume andits corresponding index relationship, the occupation of storage space can be reduced, and the storage utilization rate can be effectively improved. The invention also discloses a snapshot apparatus and system and a readable storage medium, which have the same beneficial effects as the snapshot method.

Description

technical field [0001] The invention relates to the technical field of data backup, in particular to a snapshot method, device, system and readable storage medium. Background technique [0002] With the advent of the big data era, the business data of enterprises is increasing exponentially. In some cases, even a small amount of data loss may cause huge losses. Data security has become a very important issue in various industries. For example, in banking, securities and other industries, their information systems have become an important infrastructure of the country. In this context, snapshot technology came into being. [0003] A snapshot refers to a fully available copy of a specified data set, which includes an image of the corresponding data at a certain point in time (the point in time when the copy starts). Since the snapshot initialization overhead time is very short, the creation of the snapshot can be completed in a few minutes or even tens of seconds, so the sna...

AI Technical Summary

Problems solved by technology

[0004] In the existing technology, mirror snapshots are usually used for data backup. The original data is set to consist of 8 data blocks A—H. The changes of data blocks A and G occur after snapshot 0, and the changes of B and D occur after snapshot 1. , the changes of E and G0 occurred after snapshot 2, and the changes of H occurred after snapshot 3. The principle of mirroring snapshots is as follows figure 1 As shown, each time a snapshot is taken, the modified data blocks in the previous snapshot are copied, and the unmodified data blocks are also saved. For example, data block C and data block F have not changed, but each Both C and F are saved in the snapshot. It can be seen that the mirror snapshot will cause a large amount of storage space to be occupied and waste storage space.

Images