Storage management device

• US 20050076262A1
• Filed: 02/13/2004
• Published: 04/07/2005
• Est. Priority Date: 09/23/2003
• Status: Active Grant

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Revivio, Inc. (Gen Digital Inc.)
• Inventors: Rowan, Michael T., Rodgers, Kevin F.
• Granted Patent: US 7,272,666 B2
• Time in Patent Office: Days
• US Class Current: 714/6
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery

Abstract

A method, apparatus, and system for accessing units of storage that depends at least in part on an address of the unit of storage and the time that data was written to the unit of storage. By accessing units of storage in response to a time, prior images of a data store can be generated substantially instantaneously.

Claims

1-25. -25. (canceled)

26. A storage management device, comprising:

a plurality of I/O processing modules for accessing units of storage by specifying an address and a time, each of the I/O processing modules comprising;

a target mode driver in communication with a host for receiving I/O requests;

a data classifier in communication with the target mode driver for classifying received I/O requests and extracting control information associated with the requests;

an I/O manager in communication with the data classifiers of the processing modules, the I/O manager for processing the extracted control information; and

a physical store interface in communication with the I/O managers of the processing modules, the physical store interface for communicating with at least one physical store in response to the processed control information; and

an internal network for communication among the processing modules.

27. The storage management device of claim 26 wherein the I/O manager identifies idempotent groups of control packets.

28. The storage management device of claim 27 wherein each control packet in the idempotent group of control packets has an address that is independent of the addresses of the other control packets in the group.

29. The storage management device of claim 28 wherein the extracted control information associated with each idempotent group comprises no more than one I/O operation directed to each control packet address.

30. The storage management device of claim 27 wherein the I/O manager manages I/O to insure that modified units of storage are saved and are accessible for future reference.

31. The storage management device of claim 26 wherein the I/O manager comprises a current store controller, a time store controller, and functional storage.

32. The storage management device of claim 26 wherein the I/O manager monitors and indexes an information flow within the storage management device.

33. The storage management device of claim 32 wherein the I/O manager subscribes via a subscription protocol to a plurality of specified units of storage for which it processes the extracted control information.

34. The storage management device of claim 32 wherein the I/O manager comprises functional storage comprising a map of units of storage in a data store that were overwritten subsequent to a recovery time.

35. The storage management device of claim 34 wherein the map identifies a storage location for past data.

36. The storage management device of claim 26 wherein the I/O manager comprises a plurality of time store controller modules.

37. The storage management device of claim 26 wherein the I/O manager evaluates read requests to determine whether requested units of storage were involved in a prior write operation.

38. The storage management device of claim 26 wherein the I/O manager forwards processed I/O control information to the physical store interface.

39. The storage management device of claim 27 wherein the I/O manager monitors storage management device performance and adjusts an optimization routine in response to the monitored performance.

40. The storage management device of claim 26 wherein the target mode driver comprises a Fibre Channel interface circuit.

41. The storage management device of claim 26 further comprising a buffer in communication with the target mode driver for storing the received I/O requests.

42. The storage management device of claim 41 wherein the buffer comprises random access memory (RAM).

43. The storage management device of claim 41 wherein the buffer comprises at least one disk.

44. The storage management device of claim 26 wherein the data classifier is associated with at least one I/O manager and determines whether the at least one I/O manager is subscribed to process control information for any target units of storage identified in the received I/O requests.

45. The storage management device of claim 26 wherein the physical store interface comprises a Fibre channel interface circuit.

46. The storage management device of claim 26 wherein the internal network comprises a physical network that implements a remote direct memory access modeled interface selected from a group consisting of InfiniBand, Ethernet, Fibre Channel, and SCSI.

47. The storage management device of claim 26 wherein the I/O requests are write requests and the target mode driver separates each request into control information associated with the request and a data payload.

48. The storage management device of claim 47 wherein the data payload is communicated over the internal network to the physical store interface.

49. The storage management device of claim 48 wherein the data payload is communicated to the physical store over a Fibre Channel network.

50. A method of accessing units of storage by specifying an address and a time, the method employing a storage management device comprising a plurality of I/O processing modules, the method comprising the steps of:

receiving, by a target mode driver, I/O requests from a host;

classifying, by a data classifier, received I/O requests;

extracting, by a data classifier, control information associated with the requests;

processing, by an I/O manager, the extracted control information; and

communicating, by a physical store interface, with at least one physical store to access units of storage in response to the I/O requests.

51. The method of claim 50 wherein the I/O requests comprise at least one of an address and a time specification.

52. The method of claim 50, further comprising the step of identifying idempotent groups of control packets.

53. The method of claim 52 wherein each control packet in the idempotent group of control packets has an address that is independent of the addresses of the other control packets in the group.

54. The method of claim 53 wherein the extracted control information associated with each idempotent group comprises no more than one I/O operation directed to each control packet address.

55. The method of claim 52, further comprising the step of managing I/O to insure that modified units of storage are saved and are accessible for future reference.

56. The method of claim 51, further comprising the step of monitoring and indexing an information flow within the storage management device.

57. The method of claim 56, further comprising the step of subscribing via a subscription protocol to a plurality of specified units of storage for which a specific I/O processing module processes the extracted control information.

58. The method of claim 51 wherein the I/O manager comprises functional storage comprising a map of units of storage in a data store that were overwritten subsequent to a recovery time.

59. The method of claim 58 wherein the map identifies a storage location for past data.

60. The method of claim 50 wherein the I/O processing modules further comprise a plurality of time store controller modules.

61. The method of claim 50, further comprising the step of evaluating read requests to determine whether requested units of storage were involved in a prior write operation.

62. The method of claim 50, further comprising the step of forwarding processed I/O control information to a physical store interface.

63. The method of claim 52, further comprising monitoring storage management device performance and adjusting an optimization routine in response to the monitored performance.

64. The method of claim 50 wherein the I/O processing modules comprise a Fibre Channel interface circuit.

65. The method of claim 64 wherein the communication with the physical store is via the Fibre Channel interface circuit.

66. The method of claim 50, further comprising the step of determining which I/O processing modules are subscribed to process control information for any target units of storage identified in the received I/O requests.

67. The method of claim 50 wherein the I/O processing modules communicate to one another via a physical network that implements a remote direct memory access modeled interface selected from a group consisting of InfiniBand, Ethernet, Fibre Channel, and SCSI.

68. A storage network, comprising:

multiple storage devices; and

a storage management device, comprising;

a plurality of I/O processing modules for accessing units of storage by specifying an address and a time, each of the I/O processing modules comprising;

a target mode driver in communication with a host for receiving I/O requests;

a data classifier in communication with the target mode driver for classifying received I/O requests and extracting control information associated with the requests;

an I/O manager in communication with the data classifiers of the processing modules, the I/O manager for processing the extracted control information; and

a physical store interface in communication with the I/O managers of the processing modules, the physical store interface for communicating with at least one physical store in response to the processed control information; and

an internal network for communication among the processing modules.