Storage system including storage nodes, storage controller processing data reading and writing, and volatile memory, and storage control method

Patent metadata

Field	Value
Publication number	US-12360859-B2
Application number	US-202318120015-A
Country	US
Kind code	B2
Filing date	Mar 10, 2023
Priority date	Nov 28, 2022
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

A storage system includes one or more storage nodes each having a non-volatile storage device, a storage controller, and a volatile memory, in which the storage device includes a plurality of base image storage areas including at least a first base image storage area and a second base image storage area as areas for storing entire predetermined information stored in the memory as a base image, and the storage controller starts processing to store a next base image in the second base image storage area when the base image storage with respect to the first base image storage area is complete, and reads out the storage-completed base image and restores the image to the memory in a case where the predetermined information is lost from the memory.

First claim

What is claimed is:

1. A storage system comprising one or more storage nodes each having a non-volatile storage device, a storage controller processing data reading and writing with respect to the storage device, and a volatile memory,
wherein the storage device includes a plurality of base image storage areas including at least a first base image storage area and a second base image storage area as areas for storing entire predetermined information stored in the memory as a base image,
wherein the storage controller:
performs processing to store the base image in the first base image storage area and, when the base image storage with respect to the first base image storage area is complete, starts processing to store a next base image in the second base image storage area; and
performs recovery processing to read out the storage-completed base image and restore the image to the memory in a case where the predetermined information is lost from the memory, and

wherein the storage controller:
starts processing to store a next base image in the first base image storage area when the base image storage with respect to the second base image storage area is complete, and
suppresses execution of the reading and writing processing with respect to the storage device in a case where a storage destination of the base image is in a process of switching between the first base image storage area and the second base image storage area.

2. The storage system according to claim 1 , wherein
the predetermined information is control information,
the storage device includes a plurality of log storage areas for storing update content of the control information as a log in association with the plurality of base image storage areas,
the storage controller stores the update content of the control information in a corresponding log storage area while performing processing to store a base image of the control information in one of the base image storage areas, and
during the recovery processing, the storage controller reads a storage-completed base image out of the base image storage area and writes the image to the memory and then reads a log acquired from the start of the base image storage until loss of the control information out of the log storage area and writes the log to the memory to restore the control information.

3. The storage system according to claim 1 , wherein
the predetermined information is control information,
the storage device includes a log storage area for storing update content of the control information as a log,
the storage controller records a storage position of the log storage area in response to switching of a base image storage area used as a storage destination of the base image, and
during the recovery processing, the storage controller reads a storage-completed base image out of the base image storage area and writes the image to the memory and then reads a log acquired from the start of the base image storage until loss of the control information out of the log storage area and writes the log to the memory to restore the control information.

4. The storage system according to claim 1 ,
wherein the storage controller duplicates the predetermined information present in the memory and stores the information in the base image storage area as the base image.

5. The storage system according to claim 1 ,
wherein, in a case where the storage-completed base image is present, a log related to the predetermined information is applied to the base image and storage as a new base image is performed in the base image storage area.

6. The storage system according to claim 1 , wherein
the predetermined information is control information,
the plurality of storage nodes make the control information redundant by storing the control information in each memory, and
the storage controller of each storage node stores entire control information stored in a memory of own node in the storage device as the base image.

7. The storage system according to claim 1 , wherein
the predetermined information is control information,
the storage controller of one of the plurality of storage nodes stores entire control information stored in a memory of own node in the storage device of the own node as the base image and transmits the base image to another storage node, and
the storage controller of a storage node that has received the base image from the other storage node among the plurality of storage nodes stores the received base image in the storage device of the own node.

8. The storage system according to claim 1 ,
wherein the storage controller divides and stores the base image in a plurality of the storage devices.

9. A storage system comprising one or more storage nodes each having a non-volatile storage device, a storage controller processing data reading and writing with respect to the storage device, and a volatile memory,
wherein the storage device includes a plurality of base image storage areas including at least a first base image storage area and a second base image storage area as areas for storing entire predetermined information stored in the memory as a base image,
wherein the storage controller:
performs processing to store the base image in the first base image storage area and, when the base image storage with respect to the first base image storage area is complete, starts processing to store a next base image in the second base image storage area; and
performs recovery processing to read out the storage-completed base image and restore the image to the memory in a case where the predetermined information is lost from the memory, and

wherein the storage controller:
starts processing to store a next base image in a third base image storage area when the base image storage with respect to the second base image storage area is complete,
starts processing to store a next base image in the first base image storage area when the base image storage with respect to the third base image storage area is complete, and
executes the reading and writing processing with respect to the storage device even in a case where a storage destination area for the base image is in a process of switching.

10. A storage system comprising one or more storage nodes each having a non-volatile storage device, a storage controller processing data reading and writing with respect to the storage device, and a volatile memory,
wherein the storage device includes a plurality of base image storage areas including at least a first base image storage area and a second base image storage area as areas for storing entire predetermined information stored in the memory as a base image,
wherein the storage controller:
performs processing to store the base image in the first base image storage area and, when the base image storage with respect to the first base image storage area is complete, starts processing to store a next base image in the second base image storage area; and
performs recovery processing to read out the storage-completed base image and restore the image to the memory in a case where the predetermined information is lost from the memory, and

wherein the storage controller acquires a base image stored in the base image storage area of another storage node and writes the image to a memory of own node when a failure has occurred in the storage device of the own node.

11. A storage system comprising one or more storage nodes each having a non-volatile storage device, a storage controller processing data reading and writing with respect to the storage device, and a volatile memory,
wherein the storage device includes a plurality of base image storage areas including at least a f

Assignees

• Hitachi Ltd
• Hitachi Vantara Ltd

Inventors

• Ono Taisuke
• Ohira Yoshinori
• Ito Shintaro
• Yamamoto Takahiro

Classifications

• G06F11/1471

  involving logging of persistent data for recovery · CPC title

• G06F11/1464

  for networked environments · CPC title

• G06F11/2089

  Redundant storage control functionality · CPC title

• G06F11/1469 Primary

  Backup restoration techniques · CPC title

• G06F11/1448 Primary

  Management of the data involved in backup or backup restore · CPC title