APPARATUS, SYSTEM, AND METHOD FOR AUTO-COMMIT MEMORY MANAGEMENT

• US 20130097369A1
• Filed: 12/04/2012
• Published: 04/18/2013
• Est. Priority Date: 12/13/2010
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: Fusion-IO Incorporated (Western Digital Corporation)
• Inventors: Talagala, Nisha, Sundararaman, Swaminathan, Sridharan, Srinath
• Granted Patent: US 9,047,178 B2
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/0804 with main memory updating G06F12/0806 takes precedence
• CPC Class Codes: G06F 2212/202 Non-volatile memory
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

An apparatus, system, and method are disclosed for auto-commit memory management. The method includes receiving an auto-commit request from a client, such as a barrier request or a checkpoint request. The auto-commit request is associated with an auto-commit buffer of a non-volatile recording device. The method includes issuing a serializing instruction that flushes data from a processor complex to the auto-commit buffer. The method includes determining completion of the serializing instruction flushing the data to the auto-commit buffer.

Claims

1. A method for auto-commit memory management, the method comprising:

receiving an auto-commit request from a client, the auto-commit request associated with an auto-commit buffer of a non-volatile recording device;

issuing a serializing instruction that flushes data from a processor complex to the auto-commit buffer; and

determining completion of the serializing instruction flushing the data to the auto-commit buffer.

2. The method of claim 1, further comprising ensuring persistence of data received in the processor complex for the auto-commit buffer prior to the auto-commit request in response to determining completion of the serializing instruction, the auto-commit request comprising a barrier request.

3. The method of claim 1, further comprising:

stalling operations for the auto-commit buffer between issuing the serializing instruction and determining completion of the serializing instruction; and

ensuring persistence of operations received in the processor complex for the auto-commit buffer prior to the auto-commit request, wherein the processor complex fails to ensure that each operation is completed in the same order in which the operation is received.

4. The method of claim 1, wherein determining completion of the serializing instruction comprises:

placing a completion identifier in the processor complex, the completion identifier associated with the non-volatile recording device; and

issuing a second serializing instruction to flush the completion identifier from the processor complex, wherein determining completion of the serializing instruction is in response to receiving the completion identifier in the non-volatile recording device.

5. The method of claim 4, wherein placing the completion identifier in the processor complex comprises storing the completion identifier to a virtual memory address mapped to a control status register of the non-volatile recording device, and the completion identifier is flushed to the control status register in response to the second serializing instruction.

6. The method of claim 4, further comprising copying one or more pages of the auto-commit buffer to a second location in response to receiving the completion identifier, wherein the completion identifier comprises a checkpoint indicator.

7. The method of claim 6, further comprising placing, in the processor complex, an indicator of the one or more pages of the auto-commit buffer prior to issuing the serializing instruction such that the indicator of the one or more pages is flushed to the non-volatile recording device prior to the second serializing instruction.

8. The method of claim 1, further comprising indicating completion of the auto-commit request to the client.

9. The method of claim 1, further comprising:

preserving the data in the non-volatile recording device in response to a restart event; and

providing the data from the non-volatile recording device to the client after the restart event, the data associated with a persistent unique identifier.

10. The method of claim 1, further comprising executing the serializing instruction, wherein a communications bus for the non-volatile recording device supports operation ordering and executing the serializing instruction flushes the data from the processor complex to the auto-commit buffer over the communications bus.

11. The method of claim 10, wherein the communications bus is in communication with the processor complex through one or more of a root complex and a northbridge device.

12. The method of claim 1, wherein the auto-commit buffer supports instant-commit, memory semantic operations from the client within a memory address space of a host computing device.

13. An apparatus for auto-commit memory management, the apparatus comprising:

an auto-commit buffer within an isolation zone of a non-volatile memory device, the auto-commit buffer configured to receive data destaged from a processor complex of a host computing device in response to a serializing instruction;

a barrier completion module configured to determine completion of the serializing instruction destaging the data to the auto-commit buffer; and

a checkpoint module configured to create a snapshot copy of one or more pages of the auto-commit buffer in response to completion of the serializing instruction.

14. The apparatus of claim 13, wherein the checkpoint module is configured to store the snapshot copy within the non-volatile memory device.

15. The apparatus of claim 13, wherein the checkpoint module is configured to receive an indicator of the one or more pages of the auto-commit buffer that comprise the snapshot copy, the indicator destaged from the processor complex to the non-volatile memory device in response to the serializing instruction.

16. The apparatus of claim 13, wherein the barrier completion module is configured to determine completion of the serializing instruction by receiving a completion identifier destaged from the processor complex in response to a second serializing instruction.

17. The apparatus of claim 13, further comprising a lock module configured to stall operations for the auto-commit buffer between the serializing instruction and the barrier completion module determining completion of the serializing instruction.

18. A system for auto-commit memory management, the system comprising:

a device driver for a non-volatile storage device, the device driver configured to execute on a processor of a host computing device, the device driver comprising,

an auto-commit request module configured to receive an auto-commit request for an auto-commit buffer within an isolation zone of the non-volatile storage device; and

a flush module configured to execute a serializing instruction to flush data from a cache of the processor to the auto-commit buffer in response to the auto-commit request; and

a storage controller disposed on the non-volatile storage device, the storage controller comprising,

a barrier completion module configured to determine completion of the serializing instruction flushing the data to the auto-commit buffer in response to receiving a completion identifier flushed from the cache of the processor to the non-volatile storage device.

19. The system of claim 18, wherein the device driver further comprises a driver barrier completion module in cooperation with the barrier completion module of the storage controller, the driver barrier completion module configured to:

write the completion identifier to the cache of the processor, the completion identifier associated with a virtual memory address of the host computing device, the virtual memory address mapped to the non-volatile storage device; and

issue a second serializing instruction to flush data from the cache of the processor, such that the controller barrier completion module receives the completion identifier at the non-volatile storage device.

20. The system of claim 18, wherein the storage controller further comprises a checkpoint module configured to copy one or more pages of the auto-commit buffer to a second location within the non-volatile storage device in response to the completion identifier.

21. A computer program product comprising a computer readable storage medium storing computer usable program code executable to perform operations for auto-commit memory management, the operations comprising:

issuing a first serializing instruction in response to an auto-commit request for an auto-commit buffer of a non-volatile memory device, the first serializing instruction to flush data from a processor cache to the auto-commit buffer;

placing a completion identifier in the processor cache, the completion identifier associated with the non-volatile memory device; and

issuing a second serializing instruction to flush the completion identifier from the processor cache to the non-volatile memory device such that receiving the completion identifier in the non-volatile memory device indicates completion of the first serializing instruction.

22. The computer program product of claim 21, wherein the operations further comprise creating a copy within the non-volatile memory device of one or more pages of the auto-commit buffer in response to receiving the completion identifier in the non-volatile memory device, the one or more pages identified in the auto-commit request.

23. An apparatus for auto-commit memory management, the apparatus comprising:

means for receiving an auto-commit request for an auto-commit buffer of a non-volatile recording device, a memory address range of a host mapped to the auto-commit buffer;

means for issuing a serializing instruction in response to the auto-commit request, the serializing instruction to flush data of the memory address range from a processor cache of the host to the auto-commit buffer; and

means for determining completion of the serializing instruction flushing the data of the memory address range to the auto-commit buffer.

24. The apparatus of claim 23, further comprising means for creating, within the non-volatile recording device, a snapshot copy of one or more pages of the auto-commit buffer in response to determining completion of the serializing instruction.

25. The apparatus of claim 23, further comprising:

means for preserving the data of the memory address range in the non-volatile recording device in response to a restart event; and

means for providing the data of the memory address range from the non-volatile recording device to the client after the restart event.