Method for recording mapping relation between logical extents (LE) and physical extents (PE)

Abstract

The invention discloses a method for recording mapping relation between logical extents (LE) and physical extents (PE). The method comprises the steps: after the distribution of the PE is finished, the mapping relation between the LE and the PE on a logical volume (LV) which is of thin provisioning is recorded in the unit of extent; wherein the extent comprises parameters for respectively denoting an LE initial position, a PE initial position and extent length. The method is used for recording the mapping relation between the LE and the PE with the description mode of extent, which is unrelated to SP (Service Pack) capacity and the LV capacity, and thus, the data volume for recording the mapping relation between the LE and the PE is greatly reduced greatly.

Description

technical field [0001] The invention relates to the field of storage technology, in particular to a method for recording the mapping relationship between logical segments and physical segments. Background technique [0002] With the continuous development of the information age, the capacity of information increases exponentially, and the demand for storage resources is increasing. In traditional storage management, the demand for storage resources is estimated in advance, and then logical volumes are allocated to users. However, the demand estimation of such storage resources often exceeds the required capacity actually used, which leads to waste of storage resources and increases storage costs. [0003] In this regard, people have developed thin provisioning technology, which allocates physical storage space according to actual use. As users write more and more data, the actual storage space gradually increases automatically, thereby effectively improving the utilization ...

AI Technical Summary

Problems solved by technology

[0008] Therefore, in the prior art, as the disk storage capacity increases, the amount of data used to record the mapping relationship between logical segments such as LE and PE mapping relationships and physical segments will become larger and larger, and the required memory The space is getting bigger and bigger, but limited by the size of the memory space, the current method of recording the mapping relationship between LE and PE is often unable to adapt to the storage system with lower storage granularity

In addition, because the thin provisioning technology needs to allocate specific PEs for LVs as the actual demand space increases, when an SP has multiple LVs using thin provisioning, and there are IO reads and writes at the same time, it may cause the allocation of LE corresponding PEs. In PE, the mapping relationship between them is hashed instead of continuous, resulting in reduced IO performance

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