Virtual disk drive system and method

• US 7,398,418 B2
• Filed: 03/22/2007
• Issued: 07/08/2008
• Est. Priority Date: 08/14/2003
• Status: Active Grant

• Current Assignee: Dell International LLC (Dell Technologies Inc.)
• Original Assignee: Compellent Technologies Incorporated (Dell Technologies Inc.)
• Inventors: Klemm, Michael J., Soran, Philip E., Guider, John P., Aszmann, Lawrence E.
• Primary Examiner(s): Iqbal; Nadeem
• Application Number:
  US11/689,862
• Publication Number:
  US 20070234111A1
• Time in Patent Office: 474 Days
• Field of Search: 714 6- 8, 714/13, 714/15, 714/42
• US Class Current: 714/6.22
• CPC Class Codes: G06F 11/108 Parity data distribution in semiconductor storages, e.g. in SSD
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 11/1461 Backup scheduling policy
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 11/2089 Redundant storage control functionality
• CPC Class Codes: G06F 12/02 Addressing or allocation; Relocation program address sequencing G06F9/00; arrangements for selecting an address in a digital store G11C8/00
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A disk drive system and method capable of dynamically allocating data is provided. The disk drive system may include a RAID subsystem having a pool of storage, for example a page pool of storage that maintains a free list of RAIDs, or a matrix of disk storage blocks that maintain a null list of RAIDs, and a disk manager having at least one disk storage system controller. The RAID subsystem and disk manager dynamically allocate data across the pool of storage and a plurality of disk drives based on RAID-to-disk mapping. The RAID subsystem and disk manager determine whether additional disk drives are required, and a notification is sent if the additional disk drives are required. Dynamic data allocation and data progression allow a user to acquire a disk drive later in time when it is needed. Dynamic data allocation also allows efficient data storage of snapshots/point-in-time copies of virtual volume pool of storage, instant data replay and data instant fusion for data backup, recovery etc., remote data storage, and data progression, etc.

Claims

1. A method of data progression in a disk drive system, comprising the steps of:

determining a cost of operating for each of a plurality of RAID devices;

classifying each of the plurality of RAID devices based on the cost;

continuously checking data on the RAID devices to determine whether there is data to be moved from one classification of RAID device to another; and

moving data stored on RAID devices of one classification to RAID devices of another classification.

2. The method of claim 1, wherein the cost of each of the plurality of RAID devices is based on efficiency of the RAID devices.

3. The method of claim 2, wherein the cost of each of the plurality of RAID devices is based on storage efficiency of the RAID devices.

4. The method of claim 2, wherein the cost of each of the plurality of RAID devices is further based on physical cost of the RAID devices.

5. The method of claim 1, wherein the plurality of RAID devices are classified in relation to each other.

6. The method of claim 5, further comprising rebalancing the classification of RAID devices as storage disks are added.

7. The method of claim 1, wherein continuously checking data on the RAID devices comprises determining the access pattern and storage cost of the data.

8. The method of claim 1, wherein data is moved to lower operating cost RAID devices if the data has not been recently accessed.

9. The method of claim 1, wherein data is moved to lower operating cost RAID devices if the data comprises historical snapshot data.

10. The method of claim 8, wherein data is moved to lower operating cost RAID devices if a substantial portion of the storage space on the higher operating cost RAID devices is used up.

11. The method of claim 10, wherein data is moved to lower operating cost RAID devices if the storage space on the higher operating cost RAID devices is substantially used up.

12. The method of claim 1, wherein data is moved to higher operating cost RAID devices when data in the lower operating cost RAID devices starts to be used more frequently.

13. The method of claim 1, wherein the disk drive system comprises storage space from at least one of a plurality of RAID types, such as RAID-0, RAID-1, RAID-5, and RAID-10.

14. The method of claim 13, wherein a RAID-10 device is converted into a RAID-5 device to more efficiently use physical disk space of the RAID device.

15. The method of claim 8, wherein data is moved aggressively when storage resources are low.

16. The method of claim 1, further comprising managing a page pool of storage including a separate list of free storage spaces for each classification of RAID devices.

17. A disk drive system, comprising:

a RAID subsystem comprising a pool of storage; and

a disk manager having at least one disk storage system controller configured to;

determine an operating cost of each of a plurality of RAID devices of the RAID subsystem;

check data on the plurality of RAID devices to determine whether there is data to be moved from one RAID device to another of different operating cost; and

move data stored on RAID devices of one operating cost to RAID devices of another.

18. The system of claim 17, wherein the RAID subsystem further comprises a combination of at least one of a plurality of RAID types, such as RAID-0, RAID-1, RAID-5, and RAID-10.

19. The system of claim 18, further comprising RAID types including RAID-3, RAID-4, RAID-6, and RAID-7.

20. A disk drive system capable of data progression, comprising:

calculation means for determining a cost of operating for each of a plurality of RAID devices;

classification means for classifying each of the plurality of RAID devices based on the cost;

status checking means for continuously checking data on the RAID devices to determine whether there is data to be moved from one classification of RAID device to another; and

transfer means for moving data stored on RAID devices of one classification to RAID devices of another classification.