Storage system

Patent metadata

Field	Value
Publication number	US-11669396-B2
Application number	US-202117497092-A
Country	US
Kind code	B2
Filing date	Oct 8, 2021
Priority date	Dec 27, 2018
Publication date	Jun 6, 2023
Grant date	Jun 6, 2023

Abstract

Provided is a storage system that performs inter-node movement of parity and reconfiguration of a stripe when a node configuration is changed. The storage system includes a plurality of nodes and a management unit, in which the nodes are targets for data write and read requests, form a stripe by a plurality of data stored in different nodes and parity generated based on the plurality of data, and store the parity of the stripe to which the data under the write request belongs in a node different from the plurality of nodes that store the plurality of data so as to perform redundancy; and the management unit transmits, to the node, an arrangement change request to perform the inter-node movement of the parity and the reconfiguration of the stripe when the node configuration is changed.

First claim

What is claimed is:

1. A storage system comprising:
a plurality of nodes, each of which includes a processor and a drive; and
a management unit,
wherein each of the nodes stores data in the drive, receives data write and read requests, and writes and reads the data stored in the drive of its own node;
wherein the plurality of nodes generate parity based on a plurality of pieces of data stored in different nodes, store the parity in a drive of a node different from the plurality of nodes, and form a stripe from the plurality of pieces of data and the parity generated based on the plurality of pieces of data;
wherein when a node is added or reduced, the management unit transmits an arrangement change request to the plurality of nodes, and
wherein according to the arrangement change request, the plurality of nodes move the parity, which is generated based on the data, between a node which is not added or reduced, and the added or reduced node without moving the data.

2. The storage system according to claim 1 ,
wherein according to the arrangement change request, the plurality of nodes perform reconfiguration of the stripe stored in the node which is not added or reduced, by changing a combination of the data constituting the stripe and generating parity based on the data stored in the added or reduced node and the data stored in the node which is not added or reduced.

3. The storage system according to claim 1 ,
wherein the addition or reduction of the node is to reduce the node; and
wherein the data stored in the reduced node is moved to the node which is not reduced, and the parity is generated in the moved data and stored in the node.

4. The storage system according to claim 3 ,
wherein the parity stored in the reduced node is stored in the node which is not reduced, by moving or regenerating the parity.

5. The storage system according to claim 2 ,
wherein the addition or reduction of the node is to add or reduce a site including a plurality of nodes; and
wherein according to the arrangement change request, the plurality of nodes move the parity, which is generated based on the data, between the node which is not added or reduced, and the added or reduced site without moving the data, and perform reconfiguration of the stripe stored in the node which is not added or reduced, by changing a combination of the data constituting the stripe and generating parity based on the data stored in the added or reduced site and the data stored in the node which is not added or reduced.

6. The storage system according to claim 1 ,
wherein the node stores data related to the received write request in a volume of its own node.

7. The storage system according to claim 2 ,
wherein the stripe in which the parity is moved and a stripe to be newly formed are different stripes.

8. A storage system comprising:
a plurality of nodes, each of which includes a processor and a drive; and
a management unit,
wherein each of the nodes stores data in the drive, receives data write and read requests, and writes and reads the data stored in the drive of its own node;
wherein the plurality of nodes generate parity based on a plurality of pieces of data stored in different nodes, store the parity in a drive of a node different from the plurality of nodes, and form a stripe from the plurality of pieces of data and the parity generated based on the plurality of pieces of data;
wherein when a node is added or reduced, the management unit transmits an arrangement change request to the plurality of nodes, and
wherein according to the arrangement change request, the plurality of nodes perform reconfiguration of the stripe stored in the node which is not added or reduced, by changing a combination of data constituting the stripe and generating parity based on the data stored in the added or reduced node and the data stored in the node which is not added or reduced.

9. A configuration change method for a storage system including:
a plurality of nodes, each of which includes a processor and a drive; and
a management unit;
the configuration change method comprising:
storing, by each of the nodes, data in the drive;
receiving, by each of the nodes, data write and read requests and writing and reading the data stored in the drive of its own node;
generating, by the plurality of nodes, parity based on a plurality of pieces of data stored in different nodes and storing the parity in a drive of a node different from the plurality of nodes;
forming, by the plurality of nodes, a stripe from the plurality of pieces of data and the parity generated based on the plurality of pieces of data;
when a node is added or reduced, transmitting, by the management unit, an arrangement change request to the plurality of nodes;
moving, by the plurality of nodes according to the arrangement change request, the parity, which is generated based on the data, between a node which is not added or reduced, and the added or reduced node without moving the data; and
performing, by the plurality of nodes according to the arrangement change request, reconfiguration of the stripe stored in the node which is not added or reduced, by changing a combination of the data constituting the stripe and generating parity based on the data stored in the added or reduced node and the data stored in the node which is not added or reduced.

Assignees

• Hitachi Ltd

Inventors

• Yamamoto Takahiro
• Ebara Hiroto
• Chiba Takeru
• Agetsuma Masakuni

Classifications

• G06F11/1096 Primary

  Parity calculation or recalculation after configuration or reconfiguration of the system · CPC title

• G06F11/1076 Primary

  Parity data used in redundant arrays of independent storages, e.g. in RAID systems · CPC title