Data snapshot method and device, computer equipment and storage medium

Abstract

The invention relates to a data snapshot method and device, computer equipment and a storage medium. The method comprises the steps that the capacity of data to be written in after snapshot is obtained, and the capacity of the data to be written in is compared with preset capacity; if the capacity of the to-be-written data is greater than or equal to the preset capacity, the data to be written iswritten into a snapshot volume by adopting a writing redirection mode; if the capacity of the data to be written is smaller than the preset capacity, the data to be written is written into a solid state disk by adopting a writing redirection mode; and if the background write-back thread monitors that data is written into the solid state disk, the corresponding data in the source volume is writteninto the snapshot volume in a copy-on-write mode, and the data to be written in the solid state disk is written into the source volume. According to the scheme, the random writing performance of largedata is guaranteed, and the reading performance of small data after random writing is guaranteed.

Description

technical field [0001] The present invention relates to the field of storage technology, in particular to a data snapshot method, device, computer equipment and storage medium. Background technique [0002] Snapshot is a data protection technology commonly used in distributed storage systems. The essence of snapshot is the mirror image of data at a certain point in time. It can be a copy of data or a reference to data. In existing production applications, snapshots can regularly back up and restore online data. When a user accidentally deletes data, the data can be rolled back to the previous scheduled snapshot to ensure normal business operations. Snapshot technology is becoming more and more important in applications, and data copying in several processing stages of the snapshot process is the core of the snapshot technology. [0003] Currently, there are two main ways to copy data after a snapshot. The first method of copying data after a snapshot is copy-on-write (COW ...

AI Technical Summary

Problems solved by technology

The first method of copying data after a snapshot is copy-on-write (COW for short). Go to the snapshot storage location, and then write the newly written data to the original storage location. The advantage of this method is that the read performance after the snapshot will not decrease, but the disadvantage is that the write performance after the snapshot will drop more due to the copying of the write location data; The second method of copying data after a snapshot is Redirect On Write (ROW for short). The principle is that the first write of the data after the snapshot is written directly to the new storage location, but the index of the write location data requires Point to the new storage location. The advantage of this technology is that the write performance will not decrease after the snapshot. The disadvantage is that a large number of random writes after the snapshot will cause the overall data read performance to drop significantly.

It can be seen that there are deficiencies in the post-snapshot data copy methods using COW or ROW in the prior art, so improvement is urgently needed

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