Data reading method, device, equipment and medium

Abstract

The embodiment of the invention provides a data reading method, device and equipment and a medium. The method includes the steps that when an NVME controller retrieves the physical block page PRP corresponding to the logical block number LBN from a host, the PRP is marked as a retrieved state; based on whether or not the PRP corresponding to the data sent back from a data storage device is markedas the retrieved state, the reading order of the data sent back from the data storage device is determined, wherein the reading order of the data of which the corresponding PRP is marked as the retrieved state is prior to the reading order of the data of which the corresponding PRP is not marked as the retrieved state; the data sent back from the data storage device is read according to the determined reading order.

Description

technical field [0001] The present invention relates to the technical field of data storage, in particular to a data reading method, device, equipment and medium. Background technique [0002] With the development of the production process of data storage devices (such as: SSD, that is, Solid State Drives, solid state drives), more and more data storage devices pass the built-in NVME (Non-Volatile Memory Express, non-volatile memory specification) The controller implements data transmission with the host. [0003] Usually, the logical address of data stored in the host is LBN (Logical Block Number, logical block number), and the actual physical address corresponding to the LBN is PRP (Physical Region Page, physical region page). If the host needs to process the data stored in the data storage device, it first sends a data read command to the NVME controller to read the data to be processed. Then the NVME controller retrieves from the host the PRP corresponding to the LBN o...

AI Technical Summary

Problems solved by technology

[0004] However, the data storage device usually returns data out of order, and the NVME controller reads the data returned by the data storage device sequentially, which will lead to the following problems:

[0005] When the first piece of data (with the first LBN) has been read from the data storage device, the NMVE controller has not yet retrieved the PRP corresponding to the first LBN from the host, so the NVME controller cannot temporarily retrieve the PRP corresponding to the first LBN. A piece of data is sent to the host, and if after reading the first piece of data from the data storage device, a second piece of data (with a second LBN) is read from the data storage device and the PRP of the second LBN has been Retrieve, then the second data may wait for the second data because the previous first data has not been read

Causes the NVME controller to transfer data to the host less efficiently

[0006] For example, as figure 1 As shown, it is assumed that the NVME controller has retrieved PRP0, PRP1, PRP2, and PRP3 corresponding to LBN0, LBN1, LBN2, and LBN3 respectively, and the remaining PRP4, PRP5, and PRP6 of LBN4, LBN5, and LBN6 have not been retrieved, and The order of data returned by the data storage device is LBN2, LBN4, LBN3, so the NVME controller reads the data returned by the data storage device sequentially, LBN2 can be read and sent to the host, and the PRP4 corresponding to LBN4 has not been retrieved, so it has The data of LBN4 cannot be read yet, although the PRP3 corresponding to LBN3 has been retrieved, but because the data with LBN4 has not been read, it will cause the data with LBN3 to wait

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