Data reading method, device and system

Patent metadata

Field	Value
Publication number	US-10114577-B2
Application number	US-201715708815-A
Country	US
Kind code	B2
Filing date	Sep 19, 2017
Priority date	Mar 20, 2015
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

A data reading method, a data processing device, and a data processing system are provided. The method, executed by a first control node, includes receiving a reading message forwarded by a data switching device, where the reading message is used to instruct the first control node to read first data, and the reading message is sent by a second control node to the data switching device; if a data status identifier of the first data in a first storage node is a valid identifier, reading the first data from the first storage node, and sending the read first data to the data switching device, so that the data switching device forwards the read first data to the second control node, where the valid identifier indicates that the first data on the first storage node is available. The present application ensures that the latest first data in the node group is read.

First claim

What is claimed is:

1. A data reading method, comprising:
receiving, by a first control node, a reading message from a second control node and forwarded by a data switching device, wherein the reading message is used to instruct to read first data;
reading, by the first control node, the first data from a first storage node when a data status identifier of the first data in the first storage node is a valid identifier;
resetting the data status identifier of the first data in the first storage node from the valid identifier to an undefined identifier;
recording a destination control node of the first data in the first storage node as the second control node; and
sending the read first data to the data switching device in order to be sent to the second control node,
wherein the valid identifier indicates that the first data on the first storage node is available,
wherein the undefined identifier indicates that the destination control node provides currently latest first data,
wherein a node group comprises a storage node and a control node coupled to the storage node,
wherein a maximum of one storage node in the node group stores the first data whose data status identifier is a valid identifier,
wherein the data status identifier of the first data stored in the storage node in the node group is reset to the valid identifier when the storage node in the node group stores available first data,
wherein the control node in the node group is configured to exercise read/write control on the storage node coupled to the control node,
wherein the read/write control comprises setting a data status identifier for the first data,
wherein either of the first control node or the second control node is a control node in the node group, and
wherein the first storage node is a storage node in the node group and coupled to the first control node.

2. The method according to claim 1 , further comprising setting, by the first control node, the data status identifier of the first data in the first storage node from the undefined identifier to an invalid identifier when receiving a notification message from the second control node, wherein the invalid identifier indicates that the first data in the first storage node is unavailable.

3. The method according to claim 1 , further comprising forwarding, by the first control node, the reading message to the destination control node when the data status identifier of the first data in the first storage node is the undefined identifier.

4. The method according to claim 3 , wherein forwarding, by the first control node, the reading message to the destination control node comprises:
obtaining, by the first control node, information about the destination control node; and
sending, by the first control node, the reading message to the data switching device in order to be sent to the destination control node.

5. The method according to claim 3 , further comprising setting, by the first control node, the data status identifier of the first data in the first storage node from the undefined identifier to an invalid identifier when receiving a notification message from the destination control node, wherein the invalid identifier indicates that the first data in the first storage node is unavailable.

6. The method according to claim 2 , wherein the reading message is sent by the second control node to the data switching device when the second control node needs to write updated first data to the second storage node, and the data status identifier of the first data in the second storage node is not the valid identifier.

7. The method according to claim 1 , wherein storage nodes in the node group comprise:
a memory node configured to store the first data; and
a cache node configured to store mirrored data of the first data,
wherein control nodes in the node group comprise:
a processor node bus-connected to the cache node in the node group; and
a controller coupled to the memory node,

wherein the second control node is a controller in the node group,
wherein the first control node is a processor node, in the node group, that sends a write-back message received by the second control node, and
wherein the write-back message is sent by the processor node in the node group to the controller in the node group by means of the data switching device when the data status identifier of the first data in the bus-connected cache node is the valid identifier and the first data needs to be written back to the memory node in the node group.

8. A first control node, comprising:
a processor; and
a memory coupled to the processor and storing instructions for execution by the processor, wherein the instructions instruct the processor to:
receive a reading message from a second control node and then forwarded by a data switching device, wherein the reading message is used to instruct to read first data;
read the first data from a first storage node when a data status identifier of the first data in the first storage node is a valid identifier;
reset the data status identifier of the first data in the first storage node from the valid identifier to an undefined identifier;
record a destination control node of the first data in the first storage node as the second control node; and
send the read first data to the data switching device in order to be sent to the second control node,

wherein the valid identifier indicates that the first data on the first storage node is available,
wherein the undefined identifier indicates that the destination control node provides currently latest first data,
wherein a node group comprises a storage node and a control node coupled to the storage node,
wherein a maximum of one storage node in the node group stores the first data whose data status identifier is a valid identifier,
wherein the data status identifier of the first data stored in the storage node in the node group is reset to the valid identifier when the storage node in the node group stores available first data,
wherein the control node in the node group is configured to exercise read/write control on the storage node coupled to the control node,
wherein the read/write control comprises setting a data status identifier for the first data,
wherein either the first control node or the second control node is a control node in the node group, and
wherein the first storage node is a storage node in the node group and coupled to the first control node.

9. The first control node according to claim 8 , wherein the instructions further instruct the processor to set the data status identifier of the first data in the first storage node from the undefined identifier to an invalid identifier when receiving a notification message from the second control node, wherein the invalid identifier indicates that the first data in the first storage node is unavailable.

10. The first control node according to claim 8 , wherein the instructions further instruct the processor to forward the reading message to the destination control node when the data status identifier of the first data in the first storage node is the undefined identifier.

11. The first control node according to claim 10 , wherein the instructions further instruct the processor to:
obtain information about the destination control node;
generate, according to the information about the destination control node, a unicast instruction directed to the destination control node; and
send the reading message that carries the unicast instruction to the data switching device.

12. The first control node according to claim 10 , wherein the instructions further instruct the processor to set the data status

Assignees

• Huawei Tech Co Ltd

Inventors

• Liu Hongkuan
• Zhong Laijun
• Tan Jiang

Classifications

• G06F15/173

  using an interconnection network, e.g. matrix, shuffle, pyramid, star, snowflake · CPC title

• G06F12/0806 Primary

  Multiuser, multiprocessor or multiprocessing cache systems · CPC title

• G06F12/16

  Protection against loss of memory contents {(contains no material, see G06F11/00)} · CPC title

• G06F3/0683

  Plurality of storage devices · CPC title

• G06F3/0644 Primary

  Management of space entities, e.g. partitions, extents, pools · CPC title