Method, electronic device and computer program product for data storage

Patent metadata

Field	Value
Publication number	US-11294818-B2
Application number	US-201916575479-A
Country	US
Kind code	B2
Filing date	Sep 19, 2019
Priority date	Oct 31, 2018
Publication date	Apr 5, 2022
Grant date	Apr 5, 2022

Abstract

Techniques perform data storage. Such techniques may involve writing metadata to a first cache of a first processor, the metadata indicating allocation of a storage resource to user data. Such techniques may further involve determining an address range of the metadata in the first cache. Such techniques may further involve copying only data stored in the address range in the first cache to a second cache of a second processor. Accordingly, the data transmission volume between two processors is reduced, which helps to improve the overall performance of a storage system.

First claim

We claim:

1. A method for data storage, comprising:
writing metadata to a first cache of a first processor, the metadata indicating allocation of a storage resource to received user data, wherein the storage resource is located in at least one storage disk communicably connected to the first processor, and wherein the metadata written to the first cache indicates a user logical unit number to which a disk slice of the storage disk is allocated;
determining an address range of the metadata in the first cache; and
copying only data stored in the address range in the first cache to a second cache of a second processor, wherein copying the data stored in the address range to the second cache comprises:
determining whether a size of the data exceeds a threshold size; and
in response to the size of the data being below the threshold size:
transmitting the data to a ring buffer of the second processor, and
sending to the second processor a message indicating that the data was transmitted to the ring buffer, wherein receipt of the message by the second processor causes the second processor to copy the data from the ring buffer to the second cache.

2. The method of claim 1 , wherein the metadata is discontinuously stored in the first cache, and the data copied to the second cache comprises the metadata and other data, stored in the address range, which is different from the metadata.

3. The method of claim 1 , wherein writing the metadata to the first cache comprises:
determining a target page and an auxiliary page in the first cache, the target page comprising historical metadata associated with the metadata, and the auxiliary page being allocated in association with the target page for modifying data stored in the target page; and
writing the metadata to the auxiliary page.

4. The method of claim 3 , wherein writing the metadata to the auxiliary page comprises:
determining whether a storage resource indicated by the metadata has been allocated;
in response to the storage resource having not been allocated, writing the metadata to the auxiliary page; and
copying data stored in the target page other than the historical metadata to the auxiliary page.

5. The method of claim 4 , further comprising:
in response to the storage resource having been allocated, copying data stored in the target page to the auxiliary page;
reading the historical metadata from the auxiliary page to determine the metadata based on the historical metadata; and
writing the determined metadata to the auxiliary page.

6. The method of claim 4 , further comprising:
in response to the storage resource having been allocated, reading the historical metadata from the target page to determine the metadata based on the historical metadata;
writing the determined metadata to the auxiliary page; and
copying data stored in the target page other than the historical metadata to the auxiliary page.

7. The method of claim 1 , further comprising:
in response to the size of the data exceeding the threshold size,
transmitting the data to the second cache; and
sending to the second processor a message indicating that the data is directly transmitted to the second cache.

8. The method of claim 1 , wherein the storage disk is communicably connected to the first processor through a backend bus.

9. A method for data storage, comprising:
receiving, from a first processor, data stored in a first cache of the first processor, the received data being stored within a first address range of metadata in the first cache, the metadata indicating allocation of a storage resource to received user data, wherein the storage resource is located in at least one storage disk communicably connected to the first processor, wherein the metadata written to the first cache indicates a user logical unit number to which a disk slice of the storage disk is allocated, and wherein receiving the data from the first processor comprises:
storing the received data into a ring buffer in a second processor, and
receiving a message from the first processor indicating that the data was transmitted to the ring buffer in the second processor, wherein receipt of the message causes the second processor to copy the data from the ring buffer to a second cache of the second processor;

determining a second address range of the received data in the second cache of the second processor based on the first address range; and
writing the received data to the second cache based on the second address range.

10. The method of claim 9 , wherein the metadata is discontinuously stored in the first cache, and the received data comprises the metadata and other data, stored in the address range, which is different from the metadata.

11. The method of claim 9 , wherein receiving from the first processor the data comprises:
receiving a message indicating that the data is directly transmitted to the second cache; and
receiving the data from the first cache.

12. The method of claim 9 , wherein writing the received data to the second cache comprises:
determining a mirror target page and a mirror auxiliary page in the second cache, mirror data associated with the received data being stored in the mirror target page, and the mirror auxiliary page being allocated in association with the mirror target page for modifying data stored in the mirror target page; and
writing the received data to the mirror auxiliary page.

13. The method of claim 12 , further comprising:
copying data stored in the mirror target page other than the mirror data to the mirror auxiliary page.

14. An electronic device, comprising:
a processor; and
a memory coupled to the processor, the memory having instructions stored therein, the instructions, when executed by the processor, causing the electronic device to perform acts comprising:
writing metadata to a first cache of a first processor, the metadata indicating allocation of a storage resource to received user data, wherein the storage resource is located in at least one storage disk communicably connected to the first processor, and wherein the metadata written to the first cache indicates a user logical unit number to which a disk slice of the storage disk is allocated;
determining an address range of the metadata in the first cache; and
copying only data stored in the address range in the first cache to a second cache of a second processor, wherein copying the data stored in the address range to the second cache comprises:
determining whether a size of the data exceeds a threshold size; and
in response to the size of the data being below the threshold size:
transmitting the data to a ring buffer of the second processor, and
sending to the second processor a message indicating that the data was transmitted to the ring buffer, wherein receipt of the message by the second processor causes the second processor to copy the data from the ring buffer to the second cache.

15. The electronic device of claim 14 , wherein the metadata is discontinuously stored in the first cache, and the data copied to the second cache comprises the metadata and other data, stored in the address range, which is different from the metadata.

16. The electronic device of claim 14 , wherein writing the metadata to the first cache comprises:
determining a target page and an auxiliary page in the first cache, the target page comprising historical metadata associated with the metadata, and the auxiliary page being allocated in association with the target page for modifying data stored in the target page; and
writing the metadata to the auxiliary page.

Assignees

• Emc Ip Holding Co Llc

Inventors

• Liu Yousheng
• Han Geng
• Gao Jian
• Jia Ruiyong
• Kang Jianbin

Classifications

• G06F2212/286

  Mirrored cache memory · CPC title

• G06F3/0629

  Configuration or reconfiguration of storage systems · CPC title

• G06F3/061 Primary

  Improving I/O performance · CPC title

• G06F3/0685

  Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays · CPC title

• G06F3/0683

  Plurality of storage devices · CPC title