Storage control device, storage control method, and recording medium

• US 10,620,869 B2
• Filed: 02/23/2017
• Issued: 04/14/2020
• Est. Priority Date: 03/04/2016
• Status: Active Grant

• Current Assignee: IP Wave Pte. Ltd.
• Original Assignee: NEC Corporation
• Inventors: Nakashima, Toshitaka
• Primary Examiner(s): Gebril, Mohamed M
• Application Number:
  US15/440,375
• Publication Number:
  US 20170255392A1
• Time in Patent Office: 1,146 Days
• Field of Search: 711165
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0673 Single storage device

Abstract

A storage control device according to the present invention connected to a master disk device that stores data into a plurality of segments continuously, and a plurality of copy disk devices that are copy destinations of the data, the storage control device includes: a clone processing unit that, when receiving a copy instruction for one of the copy disk devices, repeats reading and writing of each of the segments in order of address to complete copy, and that, when a first copy disk that is the copy disk device other than a later copy disk that is the specified copy disk device is during copy when receiving the copy instruction, starts copy of the later copy disk from the segment during reading, and, after the completion of reading data of the segment, performs writing into both the first copy disk and the later copy disk.

Claims

1. A storage control device connected to a master disk device that stores data and a plurality of clone disk devices to which the same data is copied from the master disk device,

the storage control device comprising:

at least one memory configured to store instructions;

at least one processor configured to execute the instructions to perform reading the data from the master disk and writing the same data to each of the plurality of the clone disks; and

a management table storing;

a read address indicating a reading segment of the master disk device from which the data is currently read,

a write address indicating a writing segment of each of the plurality of the clone disk devices into which the same data is currently written, and

a copy-start address indicating a copy-start segment of each of the plurality of the clone disk devices from which writing the same data is started,

wherein

when receiving data-copy requests into the plurality of clone disk devices asynchronously, the at least one processor executes the instructions to perform;

reading the data from the master disk,

writing the same data to each of the plurality of the clone disks in order of segmentation of each of the plurality of the clone disks from the copy-start segment,

recording the copy-start address indicating the copy-start segment,

after completion of the writing into final segments of the plurality of clone disk devices, proceeding back to first segments of the plurality of clone disk devices, and

continuing the writing the data in order of the segmentation until completion of the writing the data to a previous segment of the copy-start segment indicated by the copy-start address.

2. A non-transitory computer-readable data storage medium storing instructions executable by a storage control device to perform a method, the storage control device connected to a master disk device that stores data and a plurality of clone disk devices to which the same data is copied from the master disk, the method for performing reading the data from the master disk and writing the same data to each of the plurality of the clone disks, the method comprising:

maintaining a management table storing a read address indicating a reading segment of the master disk device from which the data is currently read, a write address indicating a writing segment of each of the plurality of the clone disk devices into which the same data is currently written, and a copy-start address indicating a copy-start segment of each of the plurality of the clone disk devices from which writing the same data is started;

when receiving data-copy requests into the plurality of clone disk devices asynchronously;

reading the data from the master disk;

writing the same data to each of the plurality of the clone disks in order of segmentation of each of the plurality of the clone disks from the copy-start segment;

recording the copy-start address indicating the copy-start segment;

after completion of the writing into final segments of the plurality of clone disk devices, proceeding back to first segments of the plurality of clone disk devices; and

continuing the writing the data in order of the segmentation until completion of the writing the data to a previous segment of the copy-start segment indicated by the copy-start address.

3. A method performable by a storage control device connected to a master disk device that stores data and a plurality of clone disk devices to which the same data is copied from the master disk device, the method for performing reading the data from the master disk and writing the same data to each of the plurality of the clone disks, the method comprising:

maintaining a management table storing a read address indicating a reading segment of the master disk device from which the data is currently read, a write address indicating a writing segment of each of the plurality of the clone disk devices into which the same data is currently written, and a copy-start address indicating a copy-start segment from which writing the same data is started;

when receiving data-copy requests into the plurality of clone disk devices asynchronously;

reading the data from the master disk;

writing the same data to each of the plurality of the clone disks in order of segmentation of each of the plurality of the clone disks from the copy-start segment;

recording the copy-start address indicating the copy-start segment;

after the completion of the writing into final segments of the plurality of clone disk devices, proceeding back to first segments of the plurality of clone disk devices; and

continuing the writing the data in order of the segmentation until completion of the writing the data to a previous segment of the copy-start segment indicated by the copy-start address.