Loosely Coupled Mass Storage Computer Cluster

• US 20090055401A1
• Filed: 02/11/2008
• Published: 02/26/2009
• Est. Priority Date: 10/24/1995
• Status: Active Grant

• Current Assignee: SeaChange International Incorporated
• Original Assignee: SeaChange International Incorporated
• Inventors: Mann, Bruce E., Ywoskus, John A., McGrath, Edward J., Carlozzi, Michael D., Trasatti, Philip J.
• Granted Patent: US 8,019,941 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/2038 with a single idle spare processing component
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: G06F 2211/1045 Nested RAID, i.e. implementing a RAID scheme in another RAID scheme
• CPC Class Codes: H04N 7/17336 Handling of requests in head-ends

Abstract

A method and apparatus redundantly store data, in particular video data objects, in a distributed computer system having at least three processor systems, each processor system being connected in point to point two way channel interconnection with each other processor system. The data is stored in a redundant fashion both at the computer system level as well as the processor system level. Accordingly, the failure of a single processor does not adversely affect the integrity of the data. The computer system can also overlay a switching system connected in a ring fashion for providing a fault tolerance to the failure of a single connected processor system at the switch level. Accordingly, there results a fault tolerant data distribution system.

Claims

1-39. -39. (canceled)

40. A data cluster, comprising:

three or more cluster members, each cluster member comprising data storage and a data storage controller;

the data storage controller responds to individual data service requests by interoperating with other data storage controllers within a set of the three or more cluster members to access the corresponding data storage to read and write data according to a distributed, redundant storage process.

41. The data cluster of claim 40 wherein the data storage controller responds to the individual data service requests from a client.

42. The data cluster of claim 41 wherein the data storage controller responds to the individual data service requests from an external client over an external link coupled to any one of the three or more cluster members.

43. The data cluster of claim 41 wherein each cluster member further comprises a data service application module that communicates the individual data service requests from the client to the data storage controller.

44. The data cluster of claim 40 wherein:

the data storage controller responds to a request to store input data in the data cluster by interoperating with the other data storage controllers to write segments of the input data across the data storage within the set of the three or more cluster members according to the distributed, redundant storage process.

45. The data cluster of claim 44 wherein the data storage within the set of the three or more cluster members comprise a shared cluster volume, one of the data storage controllers within the set of three or more cluster members is designated to control the writing of the input data segments across all of the data storage of the cluster volume.

46. The data cluster of claim 44 wherein the data storage for each cluster member is private, the data storage controller responding to the request allocates the input data segments for storage across the set of the three or more cluster members according to the distributed, redundant storage process and each of the other data storage controllers individually controls the writing of the allocated data segments to the corresponding data storage.

47. The data cluster of claim 44 wherein each data storage controller comprises:

an interface module that fragments the input data into the input data segments for storage across the data storage within the set of the three or more cluster members according to the distributed, redundant storage process.

48. The data cluster of claim 44 wherein each data storage controller comprises:

a local file provider and a remote file provider that write the input data segments across the data storage within the set of the three or more cluster members according to the distributed, redundant storage process.

49. The data cluster of claim 48 wherein the remote file provider communicates with the other data storage controllers within the set of the three or more cluster members to write the data segments in the corresponding data storage according to the distributed, redundant storage process.

50. The data cluster of claim 48 wherein the local file provider writes data segments to the data storage of the local cluster member.

51. The data cluster of claim 40 wherein:

the data storage controller responds to a request for data stored in the data cluster by interoperating with the other data storage controllers to obtain segments of the requested data stored across the data storage within the set of the three or more cluster members according to the distributed, redundant storage process.

52. The data cluster of claim 51 wherein each data storage controller comprises:

an interface module that assembles the segments of the requested data obtained from across the data storage within the set of the three or more cluster members according to the distributed, redundant storage process and delivers the requested data to a requesting device.

53. The data cluster of claim 51 wherein each data storage controller comprises:

a local file provider and a remote file provider that obtain the segments of the requested data from the data storage within the set of the three or more cluster members according to the distributed, redundant storage process.

54. The data cluster of claim 53 wherein the remote file provider communicates with the other data storage controllers within the set of the three or more cluster members to obtain the data segments in the corresponding data storage according to the distributed, redundant storage process.

55. The data cluster of claim 53 wherein the local file provider obtains segments of requested data from the data storage of the local cluster member.

56. The data cluster of claim 51 wherein:

in the presence of a failure of one of the three or more cluster members, the data storage controller responding to the request obtains segments of the requested data from active cluster members in the set, obtains segments of redundant data from the active cluster members in place of missing segments of the requested data stored at the failed cluster member, and reconstructs the missing segments using the segments of the requested data and the segments of redundant data obtained from the active cluster members.

57. The data cluster of claim 40 wherein the data is video data.

58. The data cluster of claim 40 wherein the data storage controller responds to individual data service requests by interoperating with other data storage controllers within the set of the three or more cluster members substantially in parallel to access the corresponding data storage to read and write data according to a distributed, redundant storage process.

59. The data cluster of claim 40 wherein the distributed, redundant storage process is a Redundant Array of Independent Disks (RAID) storage process.

60. The data cluster of claim 59 wherein the RAID storage process is a RAID-5 storage process.

65. The data cluster of claim 50 wherein the local file provider writes data segments to the data storage of the local cluster member accessed through a private file system.

66. The data cluster of claim 55 wherein the local file provider obtains segments of requested data from the data storage of the local cluster member accessed through a private file system.

67. The data cluster of claim 40 wherein the data is stored with metadata for accessing the data.

68. The data cluster of claim 67 wherein the metadata comprises information for determining locations of individual data blocks.

69. The data cluster of claim 67 wherein the metadata comprises one or more fragment headers, each of the one or more fragment headers being associated with at least a portion of the data.

70. The data cluster of claim 40 wherein locations of constituent blocks of the data are determined based on an individual block number to be located, fragment size, and total number of the constituent data blocks.

71. The data cluster of claim 70 wherein the fragment size equals the cluster size.

61. A data cluster, comprising:

three or more cluster members, each cluster member comprising data storage and a data storage controller;

the data storage controller responds to individual data service requests from a client by interoperating with other data storage controllers within a set of the three or more cluster members to access the corresponding data storage to read and write data according to a distributed, redundant storage process.

62. The data cluster of claim 61 wherein the data storage controller responds to the individual data service requests from an external client over an external link coupled to any one of the three or more cluster members.

63. The data cluster of claim 61 wherein each cluster member further comprises a data service application module that communicates the individual data service requests from the client to the data storage controller.

64. A method of accessing data storage within a data cluster, comprising:

providing a data cluster of three or more cluster members, each cluster member comprising data storage and a data storage controller; and

enabling the data storage controller in each cluster member to interoperate with other data storage controllers within a set of the three or more cluster members to access the corresponding data storage to read and write data according to a distributed, redundant storage process in response to individual data service requests.

72. A data cluster, comprising:

three or more cluster members, each cluster member comprising data storage and a data storage controller; and

the data storage controller responds to individual data service requests by interoperating with other data storage controllers within a set of the three or more cluster members to access the corresponding data storage to read and write data according to a distributed, redundant storage process, the data being stored with metadata for accessing the data and the metadata comprising information for determining locations of individual data blocks.

73. A method of accessing data storage within a data cluster, comprising:

providing a data cluster of three or more cluster members, each cluster member comprising data storage and a data storage controller; and

enabling the data storage controller in each cluster member to interoperate with other data storage controllers within a set of the three or more cluster members to access the corresponding data storage to read and write data according to a distributed, redundant storage process in response to individual data service requests, the data being stored with metadata for accessing the data and the metadata comprising information for determining locations of individual data blocks.

74. A data cluster, comprising:

three or more cluster members, each cluster member comprising data storage and a data storage controller; and

the data storage controller responds to individual data service requests by interoperating with other data storage controllers within a set of the three or more cluster members to access the corresponding data storage to read and write data according to a distributed, redundant storage process;

the data comprising a set of constituent data blocks, locations of the set of constituent data blocks being determined based on an individual block number to be located, fragment size, and total number of the constituent data blocks.

75. A method of accessing data storage within a data cluster, comprising:

providing a data cluster of three or more cluster members, each cluster member comprising data storage and a data storage controller; and

enabling the data storage controller in each cluster member to interoperate with other data storage controllers within a set of the three or more cluster members to access the corresponding data storage to read and write data according to a distributed, redundant storage process in response to individual data service requests;

the data comprising a set of constituent data blocks, locations of the set of constituent data blocks being determined based on an individual block number to be located, fragment size, and total number of the constituent data blocks.