Intelligent cache management

• US 20060168403A1
• Filed: 01/27/2005
• Published: 07/27/2006
• Est. Priority Date: 01/27/2005
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Kolovson, Curt
• Granted Patent: US 8,127,088 B2
• Time in Patent Office: Days
• US Class Current: 711/142
• CPC Class Codes: G06F 12/0804 with main memory updating G06F12/0806 takes precedence
• CPC Class Codes: G06F 12/0862 with prefetch
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 12/126 with special data handling, e.g. priority of data or instructions, handling errors or pinning
• CPC Class Codes: G06F 2212/6028 Prefetching based on hints or prefetch instructions
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

An exemplary storage network, storage controller, and methods of operation are disclosed. In one embodiment, a method of managing cache memory in a storage controller comprises receiving, at the storage controller, a cache hint generated by an application executing on a remote processor, wherein the cache hint identifies a memory block managed by the storage controller, and managing a cache memory operation for data associated with the memory block in response to the cache hint received by the storage controller.

Claims

1. A method of managing cache memory in a storage controller, comprising:

receiving, at the storage controller, a cache hint generated by an application executing on a remote processor, wherein the cache hint identifies a memory block managed by the storage controller; and

managing a cache memory operation for data associated with the memory block in response to the cache hint received by the storage controller.

2. The method of claim 1, wherein:

the cache hint comprises a Write Through cache hint; and

managing a cache memory operation comprises executing a fast de-stage operation on one or more data blocks identified in the cache hint.

3. The method of claim 1, wherein:

the cache hint comprises a Pin cache hint; and

managing a cache memory operation comprises holding one or more data blocks identified in the Pin cache hint until an Unpin cache hint identifying one or more data blocks identified in the Pin cache hint.

4. The method of claim 1, wherein:

the cache hint comprises a Pin cache hint; and

managing a cache memory operation comprises holding one or more data blocks identified in the Pin cache hint until a time threshold expires.

5. The method of claim 1, wherein:

the cache hint comprises a Pin cache hint; and

managing a cache memory operation comprises holding one or more data blocks identified in the Pin cache hint until a capacity threshold is reached.

6. The method of claim 1, wherein:

the cache hint comprises a Sequential Scan cache hint; and

managing a cache memory operation comprises pre-fetching from a permanent storage medium one or more data blocks identified in the Sequential Scan cache hint.

7. The method of claim 1, wherein:

the storage controller maintains a queue of data blocks for executing cache operations;

the cache hint comprises a Priority cache hint that associates a priority level for cache operations associated with one or more data blocks identified in the cache hint; and

the storage controller organizes data blocks in the queue in accordance with the priority level.

8. The method of claim 1, wherein:

the storage controller maintains logical associations for working sets of data blocks for executing cache operations;

the cache hint comprises a Working Set cache hint that identifies a working set for cache operations associated with one or more data blocks identified in the cache hint; and

the storage controller manages the data blocks identified in the cache hint as part of the Working Set identified in the cache hint.

9. The method of claim 1, further comprising acknowledging completion of a cache operation to a host computer.

10. A storage controller, comprising:

an input port to receive data operations from a remote computing device;

a processor; and

a memory module,

wherein the memory module comprises logic instructions which, when executed, configure the processor to;

receive a cache hint generated by an application executing on a remote computing device, wherein the cache hint identifies a memory block managed by the storage controller; and

manage a cache memory operation for data associated with the memory block in response to the cache hint received by the storage controller.

11. The storage controller of claim 10, wherein:

the cache hint comprises a Write Through cache hint; and

the storage controller executes a fast de-stage operation on one or more data blocks identified in the cache hint.

12. The storage controller of claim 10, wherein:

the cache hint comprises a Pin cache hint; and

the storage controller holds one or more data blocks identified in the Pin cache hint until an Unpin cache hint identifying one or more data blocks identified in the Pin cache hint.

13. The storage controller of claim 10, wherein:

the cache hint comprises a Pin cache hint; and

the storage controller holds one or more data blocks identified in the Pin cache hint until a time threshold expires.

14. The storage controller of claim 10, wherein:

the cache hint comprises a Pin cache hint; and

the storage controller holds one or more data blocks identified in the Pin cache hint until a capacity threshold is reached.

15. The storage controller of claim 10, wherein:

the cache hint comprises a Sequential Scan cache hint; and

the storage controller pre-fetches from a permanent storage medium one or more data blocks identified in the Sequential Scan cache hint.

16. The storage controller of claim 10, wherein:

the storage controller maintains a queue of data blocks for executing cache operations;

the cache hint comprises a Priority cache hint that associates a priority level for cache operations associated with one or more data blocks identified in the cache hint; and

the storage controller organizes data blocks in the queue in accordance with the priority level.

17. The storage controller of claim 10, wherein:

the storage controller maintains logical associations for working sets of data blocks for executing cache operations;

the cache hint comprises a Working Set cache hint that identifies a working set for cache operations associated with one or more data blocks identified in the cache hint; and

the storage controller manages the data blocks identified in the cache hint as part of the Working Set identified in the cache hint.

18. The storage controller of claim 10, further comprising acknowledging completion of a cache operation to a host computer.

19. A storage device, comprising:

at least one array of disk drives;

a controller to manage data input/output operations between the array of disk drives and a remote processor; and

a cache memory module communicatively connected to the controller,

wherein the controller receives a cache hint generated by an application executing on a remote computing device and manages data operations in the cache memory based on the cache hint received by the controller.

20. The storage device of claim 19, wherein:

the cache hint comprises a Write Through cache hint; and

the controller executes a fast de-stage operation on one or more data blocks identified in the cache hint.

21. The storage device of claim 19, wherein:

the cache hint comprises a Pin cache hint; and

the controller holds one or more data blocks identified in the Pin cache hint until an Unpin cache hint identifying one or more data blocks identified in the Pin cache hint is received.

22. The storage device of claim 19, wherein:

the cache hint comprises a Pin cache hint; and

the controller holds one or more data blocks identified in the Pin cache hint until a time threshold expires.

23. The storage device of claim 19, wherein:

the cache hint comprises a Pin cache hint; and

the controller holds one or more data blocks identified in the Pin cache hint until a capacity threshold is reached.

24. The storage device of claim 19, wherein:

the cache hint comprises a Sequential Scan cache hint; and

managing a ache memory operation comprises pre-fetching from a permanent storage medium one or more data blocks identified in the Sequential Scan cache hint.

25. The storage device of claim 19, wherein:

the storage controller maintains a queue of data blocks for executing cache operations;

the cache hint comprises a Priority cache hint that associates a priority level for cache operations associated with one or more data blocks identified in the cache hint; and

the storage controller organizes data blocks in the queue in accordance with the priority level.

26. The storage device of claim 19, wherein:

the storage controller maintains logical associations for working sets of data blocks for executing cache operations;

the cache hint comprises a Working Set cache hint that identifies a working set for cache operations associated with one or more data blocks identified in the cache hint; and

the storage controller manages the data blocks identified in the cache hint as part of the Working Set identified in the cache hint.

27. The storage device of claim 19, further comprising acknowledging completion of a cache operation to a host computer.

28. A storage controller, comprising:

an input port to receive data operation from a remote computing device;

means for receiving a cache hint generated by an application executing on a remote computing device, wherein the cache hint identifies a memory block managed by the storage controller; and

means for managing a cache memory operation for data associated with the memory block in response to the cache hint received by the storage controller.