Patent ID: 9213721
Filing Date: 2015-12-15
Classification: G06F

Abstract:
1. A computer-implemented method of providing a client with access to a specified file stored in tiered storage including solid-state drive primary storage and magnetic disk drive secondary storage, said computer-implemented method comprising the steps of: (a) creating a specified file in the solid-state drive primary storage; and (b) after the specified file has been created in the solid-state drive primary storage, moving the specified file from the solid-state drive primary storage to the magnetic disk drive secondary storage, and creating a corresponding stub file in the solid-state drive primary storage, the corresponding stub file containing file mapping metadata of the specified file in the magnetic disk drive secondary storage, the file mapping metadata of the specified file in the corresponding stub file mapping an extent of data in the specified file to a logical block address of magnetic disk drive secondary storage containing data of the specified file in the magnetic disk drive secondary storage; and thereafter (c) responding to a request from the client for reading data of the specified file by reading the file mapping metadata from the corresponding stub file to obtain the logical block address of the magnetic disk drive secondary storage containing the data of the specified file, and reading the data of the specified file from the logical block address of the magnetic disk drive secondary storage containing the data of the specified file, and returning to the client the data of the specified file read from the logical block address of the magnetic disk drive secondary storage containing the data of the specified file, wherein the corresponding stub file is created in the solid-state drive primary storage in response to read access to the specified file after the specified file has been moved from the solid-state drive primary storage to the magnetic disk drive secondary storage.