Method for cache writing, cache device and storage system

Abstract

An embodiment of the present invention provides a cache write method, a cache device, and a storage system. The method includes: updating at least one piece of metadata in memory; acquiring at least one metadata group to which the at least one piece of metadata belongs; if the If the write state of the first metadata group in the at least one metadata group is a non-write state and there are multiple write IO request commands waiting to execute the metadata write operation under the first metadata group, then the The multiple write IO request commands are moved to the merged write metadata queue of the first metadata group; the metadata of the first metadata group is written into the first metadata group in the Flash In the corresponding metadata block; for multiple write IO request commands under the combined write metadata queue of the first metadata group, return the status of whether the writing of the first metadata group is successful. The method, device and system of the embodiments of the present invention can reduce the number of times of writing metadata to Flash to a certain extent.

Description

technical field [0001] Embodiments of the present invention relate to the field of data storage, and more specifically, relate to a method for caching writes, a caching device, and a storage system. Background technique [0002] Nowadays, the industry adopts the existing technology. Since the storage medium of the cache (Cache) is based on NVRAM or NVDIMM, these storage medium characteristics can well meet the small IO performance of the system, especially for metadata. [0003] Usually the size of a piece of metadata is generally between 30B-64B. When Flash is used as the storage medium of the Cache, each write request requires 2 IOs to ensure data security. The lifespan of Flash is directly related to the number of writes. If each metadata is directly IO according to the size of the metadata, the performance of Flash cannot be fully utilized. If the metadata is IO according to the size of 4K alignment, there may be a problem of write amplification. , will greatly affect ...

AI Technical Summary

Problems solved by technology

The lifespan of Flash is directly related to the number of writes. If each metadata is directly IO according to the size of the metadata, the performance of Flash cannot be fully utilized. If the metadata is IO according to the size of 4K alignment, there may be a problem of write amplification. , will greatly affect the life of the entire Flash

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