Cache management

• US 10,296,240 B2
• Filed: 04/28/2014
• Issued: 05/21/2019
• Est. Priority Date: 04/28/2014
• Status: Expired due to Fees

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Inventors: DeNeui, Nathaniel S, White, Michael, Plank, Jeffrey A
• Primary Examiner(s): Alsip, Michael
• Assistant Examiner(s): Russell, Andrew
• Application Number:
  US15/117,585
• Publication Number:
  US 20160357463A1
• Time in Patent Office: 1,849 Days
• CPC Class Codes: G06F 12/0888 using selective caching, e.g. bypass
• CPC Class Codes: G06F 2212/6046 Using a specific cache allocation policy other than replacement policy
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A storage controller for cache management that includes a cache memory and a cache management module. The cache management module to, on receipt of region specification requests from hosts, extract from the region specification requests cache rules for management of regions of data storage of a storage array, and on receipt of data operation requests from hosts, process the data operation requests based on the extracted cache rules.

Claims

1. A storage controller for cache management, the storage controller comprising:

a cache memory; and

a cache management module to;

in response to receipt of a region specification request from a host that contains cache rules and no read or write operation commands, extract from the region specification request the cache rules for management of the cache memory and regions of data storage of a storage array,

subsequent to the receipt of the region specification request, receive a data operation request from the host to read data from or write data to the data storage of the storage array, wherein the data operation request contains a read or write operation command with no additional cache rules, and

in response to receipt of the data operation request from the host, process the data operation request based on the cache rules received from the host,

wherein the cache rules received from the host comprise a cache rule to control whether the storage controller is to wait to store the data, from the host for a given region of the regions of data storage, to the cache memory based on a state of the cache memory.

2. The storage controller of claim 1, wherein the cache management module is to receive the region specification request that specifies behavior of the cache memory with respect to specific regions of storage associated with logical block address (LBA) of storage.

3. The storage controller of claim 1, wherein the cache management module is to receive the data operation request from the host that includes at least one of a write request that includes data to write to storage and identification of specific regions of the data storage to write the data and a read request that includes identification of the specific regions of the data storage to read the data, and wherein the cache management module is to compare the specific regions identified from the data operation request with a list of regions received from the region specification request.

4. The storage controller of claim 1, wherein the cache rules received from the host further comprise a cache rule to flush a given region of the regions of data storage upon occurrence of a condition.

5. The storage controller of claim 1, wherein the cache rule to control whether the storage controller waits to accept data from the host comprises a rule to cause the storage controller to not wait to accept the data in response to space for the data for the given region not being available in the cache memory.

6. The storage controller of claim 1, wherein the cache rule to control whether the storage controller waits to accept data from the host comprises a rule to cause the storage controller to wait to accept the data in response to space for the data for the given region not being available in the cache memory.

7. The storage controller of claim 1, wherein the extracted cache rules further comprise a rule to identify first data having a higher priority than second data.

8. The storage controller of claim 1, wherein the storage controller comprises:

a processor; and

a memory to store instructions that, when executed by the processor, cause the processor to provide the cache management module.

9. The storage controller of claim 1, wherein:

the region specification request is associated with the given region of the regions of the data storage of the storage array;

the cache management module is to extract a given cache rule of the cache rules from the region specification request;

the data operation request is associated with the given region; and

the cache management module is to process the data operation request based on the extracted given cache rule.

10. The storage controller of claim 9, wherein the region specification request is separate from the data operation request.

11. The storage controller of claim 1, wherein the cache rules received from the host further comprise at least one of a cache rule to store the data to the data storage of the storage array and bypass the cache memory, a cache rule to store the data to the cache memory based on an availability of space of the cache memory, and a cache rule to store the data to the cache memory in a non-persistent manner in the cache memory.

12. A method of cache management, the method comprising:

in response to receiving a region specification request from a host that contains cache rules and no read or write operation commands, extracting from the region specification request, by a processor, cache rules for management of a cache memory and regions of data storage of a storage array;

subsequent to receiving the region specification request, receiving a data operation request from the host to read data from or write data to the data storage of the storage array, wherein the data operation request contains a read or write operation command with no additional cache rules; and

in response to receiving the data operation request from the host, processing, by the processor, the data operation request based on the cache rules received from the host,

wherein the cache rules received from the host comprise a cache rule to control whether the storage controller is to wait to store the data, from the host for a given region of the regions of data storage, to the cache memory based on a state of the cache memory.

13. The method of claim 12, wherein the data operation request includes at least one of host requests to read data from storage and write data to storage.

14. The method of claim 12, wherein the region specification request specifies behavior of the cache memory with respect to specific regions of storage associated with logical block address (LBA) of storage.

15. The method of claim 12, wherein the data operation request received from the host includes at least one of a write request that includes data to write to storage and identification of specific regions of the data storage to write the data and a read request that includes identification of the specific regions of the data storage to read the data, and wherein the method further comprises:

comparing the specific regions from the data operation request with a list of regions received from the region specification request.

16. The method of claim 12, wherein the cache rules received from the host further comprise at least one of a cache rule to store the data to the data storage of the storage array and bypass the cache memory, a cache rule to store the data to the cache memory based on an availability of space of the cache memory, and a cache rule to store the data to the cache memory in a non-persistent manner in the cache memory.

17. A non-transitory computer-readable medium having computer executable instructions stored thereon for cache management, the instructions are executable by a processor to:

in response to receipt a region specification request from a host that contains cache rules and no read or write operation commands, extract from the region specification request the cache rules for management of a cache memory and regions of data storage of a storage array;

subsequent to the receipt of the region specification request, receive a data operation request from the host to read data from or write data to the data storage of the storage array, wherein the data operation request contains a read or write operation command with no additional cache rules; and

in response to the receipt of the data operation request from the host, process the data operation request based on the cache rules received from the host,

wherein the cache rules received from the host comprise a cache rule to control whether the storage controller is to wait to store the data, from the host for a given region of the regions of data storage, to the cache memory based on a state of the cache memory.

18. The non-transitory computer-readable medium of claim 17, further comprising instructions that if executed cause the processor to receive the region specification request that specifies behavior of the cache memory with respect to specific regions of storage associated with logical block address (LBA) of storage.

19. The non-transitory computer-readable medium of claim 17, further comprising instructions that if executed cause the processor to receive data operation request from the host that includes at least one of a write request that includes data to write to storage and identification of specific regions of the data storage to write the data and a read request that includes identification of the specific regions of the data storage to read the data, and compare the specific regions from the data operation request with a list of regions received from the region specification request.

20. The non-transitory computer-readable medium of claim 17, wherein the cache rules received from the host further comprise at least one of a cache rule to store the data to the data storage of the storage array and bypass the cache memory, a cache rule to store the data to the cache memory based on an availability of space of the cache memory, and a cache rule to store the data to the cache memory in a non-persistent manner in the cache memory.