Apparatus, system, and method for managing concurrent storage requests

• US 8,412,904 B2
• Filed: 03/29/2011
• Issued: 04/02/2013
• Est. Priority Date: 12/06/2006
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: Fusion-IO Incorporated (Western Digital Corporation)
• Inventors: Flynn, David, Thatcher, Jonathan, Zappe, Michael
• Primary Examiner(s): Dudek, Jr., Edward
• Assistant Examiner(s): Fishburn, John P
• Application Number:
  US13/075,000
• Publication Number:
  US 20110179225A1
• Time in Patent Office: 735 Days
• Field of Search: None
• US Class Current: 711/168
• CPC Class Codes: G06F 1/183 Internal mounting support structures, e.g. for printed circuit boards, internal connecting means for buses G06F13/409
• CPC Class Codes: G06F 11/108 Parity data distribution in semiconductor storages, e.g. in SSD
• 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 12/0868 Data transfer between cache memory and other subsystems, e.g. storage devices or host systems
• CPC Class Codes: G06F 12/12 Replacement control
• CPC Class Codes: G06F 12/121 using replacement algorithms
• CPC Class Codes: G06F 12/123 with age lists, e.g. queue, most recently used [MRU] list or least recently used [LRU] list
• CPC Class Codes: G06F 13/28 using burst mode transfer, e.g. direct memory access DMA, cycle steal G06F13/32 takes precedence
• CPC Class Codes: G06F 13/4022 using switching circuits, e.g. switching matrix, connection or expansion network G06F13/4009 takes precedence
• CPC Class Codes: G06F 13/426 using an embedded synchronisation, e.g. Firewire bus, Fibre Channel bus, SSA bus
• CPC Class Codes: G06F 2211/002 Bus
• CPC Class Codes: G06F 2211/103 Hybrid, i.e. RAID systems with parity comprising a mix of RAID types
• CPC Class Codes: G06F 2212/1032 Reliability improvement, data loss prevention, degraded operation etc
• CPC Class Codes: G06F 2212/1044 Space efficiency improvement
• CPC Class Codes: G06F 2212/2022 Flash memory
• CPC Class Codes: G06F 2212/222 Non-volatile memory
• CPC Class Codes: G06F 2212/70 Details relating to dynamic memory management
• CPC Class Codes: G06F 2212/7203 Temporary buffering, e.g. using volatile buffer or dedicated buffer blocks
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 2212/7208 : Multiple device management, e.g. distributing data over multiple flash devices
• CPC Class Codes: G06F 3/0604 : Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0608 : Saving storage space on storage systems
• CPC Class Codes: G06F 3/0613 : in relation to throughput
• CPC Class Codes: G06F 3/0619 : in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0643 : Management of files
• CPC Class Codes: G06F 3/065 : Replication mechanisms
• CPC Class Codes: G06F 3/0652 : Erasing, e.g. deleting, data cleaning, moving of data to a wastebasket
• CPC Class Codes: G06F 3/0656 : Data buffering arrangements
• CPC Class Codes: G06F 3/0659 : Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0679 : Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G06F 3/0685 : Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays
• CPC Class Codes: G06F 3/0688 : Non-volatile semiconductor memory arrays
• CPC Class Codes: G06F 9/52 : Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: G06F 9/54 : Interprogram communication
• CPC Class Codes: H04L 67/02 : based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/1097 : for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H05K 7/1444 : Complex or three-dimensional-arrangements; Stepped or dual mother boards
• CPC Class Codes: H05K 7/1487 : Blade assemblies, e.g. blade cases or inner arrangements within a blade
• CPC Class Codes: Y02D 10/00 : Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

Apparatus, systems, and methods are disclosed for managing concurrent storage requests. A multiple storage request receiver module is configured to recognize at least two storage requests from clients for data in storage devices of a storage device set. The at least two concurrent storage requests address a common portion of data. A sequencer module is configured to determine a first storage request and a second storage request from the concurrent storage requests by way of selection criteria. The sequencer module is configured to ensure completion of the first storage request prior to executing the second storage request by receiving an acknowledgment from each of the storage devices of the storage device set that received portions of the first storage request. The portions may be sent to the storage devices to execute the first storage request.

Claims

1. A method for managing concurrent storage requests in a RAID group, the method comprising:

receiving concurrent storage requests for data in storage devices of a storage device set, the concurrent storage requests comprising two storage requests, each concurrent storage request received from a client, the storage device set comprising autonomous storage devices forming a RAID group, the two concurrent storage requests addressing a common portion of data;

determining a first storage request and a second storage request from the concurrent storage requests by way of selection criteria; and

ensuring completion of the first storage request prior to executing the second storage request by receiving an acknowledgment from each of the storage devices that received portions of the first storage request, the portions sent to the storage devices to execute the first storage request.

2. The method of claim 1, wherein ensuring completion of the first storage request comprises determining completion of the portions of the first storage request sent to the storage devices to execute the first storage request.

9. The method claim 1, further comprising:

determining the storage devices to execute the first storage request; and

sending the portions of the first storage request to the determined storage devices, the portions of the first storage request each comprising a subcommand derived from the first storage request and directing the determined storage devices to transfer data for the storage request.

10. The method of claim 9, wherein the determined storage devices transfer the data of the storage request using one of Direct Memory Access (“

DMA”

) and Remote Direct Memory Access (“

RDMA”

).

11. The method of claim 9, wherein each determined storage device transfers data of the first storage request directly from the client according to the subcommand in response to receiving the subcommand.

12. The method of claim 9, further comprising transferring data of the first storage request from the client to a particular storage device of the storage device set, wherein each determined storage device transfers at least a portion of the data of the first storage request from the particular storage device, the particular storage device receiving the first storage request from the client.

13. The method of claim 9, wherein a particular storage device receives at least the first storage request from the client, the particular storage device comprising a master controller configured to coordinate execution of the first storage request.

3. A method for managing concurrent storage requests in a RAID group, the method comprising:

recognizing first and second concurrent storage requests at a particular storage device in a storage device set, the storage device set comprising autonomous storage devices forming a RAID group, the first and second concurrent storage requests received from a client and addressing a common portion of data, the first storage request arriving prior to the second storage request; and

ensuring completion of the first storage request prior to executing the second storage request by receiving an acknowledgement from each of the storage devices that received portions of the first storage request, the portions sent from the particular storage device to storage devices in the storage device set to execute the first storage request.

4. The method of claim 3, wherein an acknowledgment from a storage device acknowledges completion of a portion of the first storage request by the storage device.

5. The method of claim 3, wherein each storage device that received a portion of the first storage request transfers data of the storage request using one of Direct Memory Access (“

DMA”

) and Remote Direct Memory Access (“

RDMA”

).

6. The method of claim 3, wherein each storage device that received a portion of the first storage request transfers data of the storage request directly from the client according to the portion in response to receiving the portion.

7. The method of claim 3, further comprising transferring data for the storage request from the client to the particular storage device, wherein each storage device that received a portion of the first storage request transfers at least a portion of the data of the storage request from the particular storage device.

8. The method of claim 3, wherein the particular storage device comprises a master controller configured to ensure completion of the first storage request prior to executing the second storage request.

14. An apparatus for managing concurrent storage requests, the apparatus comprising:

a multiple storage request receiver module configured to recognize at least two concurrent storage requests from clients for data in storage devices of a storage device set, the at least two concurrent storage requests addressing a common portion of data;

a sequencer module configured to determine a first storage request and a second storage request from the concurrent storage requests by way of selection criteria, the sequencer module configured to ensure completion of the first storage request prior to executing the second storage request by receiving an acknowledgment from each of the storage devices of the storage device set that received portions of the first storage request, the portions sent to the storage devices to execute the first storage request.

15. The apparatus of claim 14, further comprising a striping module configured to divide data of the first storage request into data segments associated with the portions of the first storage request, each data segment for writing to a separate storage device of the storage device set.

16. The apparatus of claim 14, further comprising a parity-mirror module configured to write parity data for the first storage request to one or more parity-mirror storage devices within the storage device set, the parity-minor storage devices being in addition to the storage devices that received portions of the first storage request.

17. The apparatus of claim 16, further comprising a parity alternation module configured to alternate, for each of a plurality of stripes, which storage device within the storage device set is assigned to be the one or more parity-minor storage devices.

18. The apparatus of claim 14, further comprising a master validation module configured to confirm that a master controller is available to control execution of the at least two concurrent storage requests, the at least two concurrent storage requests received by other master controllers.

19. The apparatus of claim 14, further comprising a master determination module configured to determine which master controller of a group of master controllers is assigned to execute the first storage request.

20. The apparatus of claim 14, further comprising a master error module configured to return an error in response to one or more of:

a master controller receiving a storage request not controlled by the master controller; and

determining that a master controller is no longer assigned to execute the first storage request at a time of the completion of the first storage request.