Video distribution system using dynamic disk load balancing with variable sub-segmenting

• US 7,039,784 B1
• Filed: 12/20/2001
• Issued: 05/02/2006
• Est. Priority Date: 12/20/2001
• Status: Active Grant

• Current Assignee: InfoValue Computing, Inc.
• Original Assignee: InfoValue Computing, Inc.
• Inventors: Duan, Dah-Weih, Chen, Monsong, Mukherjee, Bodhi, Pappu, Aparna
• Primary Examiner(s): Anderson, Matthew D.
• Assistant Examiner(s): PATEL, HETUL B
• Application Number:
  US10/027,991
• Time in Patent Office: 1,594 Days
• Field of Search: 711170-173, 709212-219, 709231-232, 718/104, 707/205
• US Class Current: 711/170
• CPC Class Codes: G06F 2206/1012 Load balancing
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0638 Organizing or formatting or addressing of data
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: H04N 21/2181 comprising remotely distributed storage units, e.g. when movies are replicated over a plurality of video servers distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS], H04L67/1097
• CPC Class Codes: H04N 21/23103 using load balancing strategies, e.g. by placing or distributing content on different disks, different memories or different servers storage management G06F3/0604; allocation of resources considering the load in multiprogramming arrangements G06F9/505; techniques for rebalancing the load in a distributed system G06F9/5083; access to distributed or replicated servers, e.g. load balancing, in data networks H04L67/1001
• CPC Class Codes: H04N 21/23116 involving data replication, e.g. over plural servers synchronization of replicated data G06F11/1658; error detection or correction by means of data replication G06F11/2053; replication in distributed file systems G06F16/10; replication in distributed file systems G06F16/27; replication or mirroring of data in data networks H04L67/1095
• CPC Class Codes: H04N 21/2312 Data placement on disk arrays data placement in general G06F3/0604
• CPC Class Codes: H04N 21/2326 Scheduling disk or memory reading operations
• CPC Class Codes: H04N 21/47202 for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/8456 by decomposing the content in the time domain, e.g. in time segments
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99956 File allocation

Abstract

A method and apparatus for dynamically balancing the loading of video data storage devices facilitates the transfer of video data by acquiring a listing of locations and loading of all segments of a requested video data. Those storage devices containing copies of each segment of the video data having a least loading are selected. If the loading of the storage devices exceed their maximum capacity, the segment is divided into sub-segments and stored to storage devices with minimum loading. The presence of all segments of the requested video data is determined. If there are missing segments of the requested video data, each of those missing segments is assigned a file identification and file location, such that those missing segments are retrieved from a back-up storage device and assigned to data storage devices having the least loading for transfer to a requesting computer system.

Claims

1. A method for balancing a loading of a data storage devices attached to multiple computing systems during transfer of a requested data object to or from said data storage devices, comprising the steps of:

acquiring a listing of locations of all segments of the requested data object including all copies of said segments of the requested data object;

evaluating the loading of the data storage devices attached to the multiple computing systems containing all copies of all segments of the requested data object;

selecting data storage devices containing copies of each segment of the requested data object having a least loading and is less than a maximum loading for said data storage devices;

if the loading of the data storage devices is greater than the maximum loading for said storage devices, generating a sub-segment list for any segment of the requested data object residing on said data storage device would have a loading greater than the maximum loading if said segment of the requested data object were transferred, determining a load margin for all available storage devices, assigning locations for each sub-segment on each available data storage device having the least loading, and assigning file names to each sub-segment;

selecting said each available data storage device containing each segment and sub-segment; and

transferring those segments of said requested data object to a requesting computer system.

2. The method of claim 1 wherein generating the new sub-segment list comprises the steps of:

determining a number of all available data storage devices that may retain a plurality of sub-segments of said sub-segment of the requested data object;

determining a maximum data object transfer load for the available data storage devices;

assigning a minimum sub-segment size which is the smallest amount of data to be contained within one sub-segment of the segment;

calculating a first sub-segment size as a first function of a number of the data storage devices, the current digital data transfer load, the maximum digital data transfer load, and the minimum sub-segment size;

assigning a last sub-segment size as the minimum sub-segment size;

calculating all remaining sub-segment sizes as a second function of the number of the data storage devices, the current digital data transfer load, the maximum data object transfer load, and the minimum sub-segment size; and

partitioning said segment into sub-segments whereby the first sub-segment of the segment is of the first sub-segment size, the last sub-segment of the segment is of the last sub-segment size, and all the remaining sub-segments of the segment is of the remaining sub-segment sized.

3. The method of claim 2 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load, and

C_I is the current data object transfer load.

4. The method of claim 2 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load, and

C_I is the current data object transfer load.

5. The method of claim 2 wherein generating the new sub-segment list further comprises the step of:

determining a file interactivity factor describing a number of jumps by the second computing system within the data object.

6. The method of claim 5 wherein the first function is further dependent upon the file interactivity factor.

7. The method of claim 6 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file interactivity factor.

8. The method of claim 5 wherein the second function is further dependent upon the file interactivity factor.

9. The method of claim 8 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file Inter activity factor.

10. The method of claim 9 wherein the second function is further dependent upon the file usage factor.

11. The method of claim 10 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

12. The method of claim 2 wherein generating the new sub-segment list further comprises the step of:

determining a file usage factor describing a number of requests for said data object for a period of time.

13. The method of claim 12 wherein the first function is further dependent upon the file usage factor.

14. The method of claim 13 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

15. The method of claim 2 wherein generating the new sub-segment list further comprises the steps of:

determining a file usage factor describing a number of requests for said data object for a period of time; and

determining a file interactivity factor describing a number of jumps by the second computing system within the data object.

16. The method of claim 15 wherein the first function is further dependent upon the file usage factor and the file interactivity factor.

17. The method of claim 16 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f−

N_d+(M_I/M_I−

C_I)+H+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load,

H is the file usage factor, and

I is the file Inter activity factor.

18. The method of claim 15 wherein the second function is further dependent upon the file usage factor and the file interactivity factor.

19. The method of claim 18 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

20. The method of claim 1 further comprising the steps of:

determining the presence of all segments and sub-segments of the requested data object;

if there are missing segments and sub-segments of the requested data object, assigning each of those missing segments and sub-segments a file identification and file location, such that those missing segments and sub-segments are assigned to data storage devices having the least loading; and

retrieving those missing segments and sub-segments from a back-up data storage device.

21. The method of claim 1 wherein selecting the data storage devices containing copies of the segments of the requested data object and having the least loading comprises the steps of:

setting a current segment indicator to indicate which of the segments of the data object is to be transferred next;

setting a current data storage device indicator to specify a primary location of the segment to be transferred next;

if the transfer of said segment causes the loading of the data storage device containing said segment to be exceeded, incrementing the current data storage device indicator to a next location of the segment to be transferred; and

repeatedly incrementing said current data storage device indicator until said loading is not exceeded.

22. The method of claim 1 wherein transferring of the segments of the data object comprises the actions of reading said segments from the data storage device, writing said segments to the data storage device, and copying said segments from a said data storage device to an alternate data storage device, whereby said loading of the data storage device is allocated between the reading, writing, and copying of the segments to prevent interference with said reading of the segments.

23. The method of claim 1 wherein the requested data object is a video data file to be streamed isochronously to the requesting computer system.

24. A data object service system in communication with a plurality of computing systems to provide at least one data object of plurality of data objects to at least one of the plurality of computing system, comprising:

a plurality of data object storage devices in communication with each other and with any of the plurality of computing systems; and

a load balancing apparatus in communication with the plurality of data object storage devices to balance a loading of said data object storage devices during transfer of said data objects,

whereby said load balancing apparatus comprises;

a load evaluator to assess the loading of the data object storage devices containing segments of said data objects,

a data object storage device selector to create a selection list to indicate selection of those data object storage devices containing copies of each segment of a requested data object having the least loading, and

a copying initiator to initiate a copying and further segmenting of a segment of the data object to an alternate data object storage devices having low loading if all data object storage devices containing said segment have a loading greater than a maximum loading, whereby said copying initiator generates a sub-segment list for any segment of the requested data object residing on said data object storage device that would have a loading greater than the maximum loading if said segment of the requested data object were transferred, determines a load margin for all available data object storage devices, assigns locations for each sub-segment on each available data object storage device having the least loading, and assigns file names to each sub-segment.

25. The system of claim 24 wherein generating the new sub-segment size comprises the steps of:

determining a number of all available data object storage devices that may retain a plurality of sub-segments of said sub-segment of the requested data object;

determining a maximum data object transfer load for the available data object storage devices;

assigning a minimum sub-segment size which is the smallest amount of data to be contained within one sub-segment of the segment;

calculating a first sub-segment size as a first function of a number of the data object storage devices, the current digital data transfer load, the maximum digital data transfer load, and the minimum sub-segment size;

assigning a last sub-segment size as the minimum sub-segment size;

calculating all remaining sub-segment sizes as a second function of the number of the data object storage devices, the current digital data transfer load, the maximum data object transfer load, and the minimum sub-segment size; and

partitioning said segment into sub-segments whereby the first sub-segment of the segment is of the first sub-segment size, the last sub-segment of the segment is of the last sub-segment size, and all the remaining sub-segments of the segment is of the remaining sub-segment sized.

26. The system of claim 25 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load, and

C_I is the current data object transfer load.

27. The system of claim 25 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load, and

C_I is the current data object transfer load.

28. The system of claim 25 wherein generating the new sub-segment list further comprises the step of:

determining a file interactivity factor describing a number of jumps by the second computing system within the data object.

29. The system of claim 28 wherein the first function is further dependent upon the file interactivity factor.

30. The system of claim 29 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file interactivity factor.

31. The system of claim 28 wherein the second function is further dependent upon the file interactivity factor.

32. The system of claim 31 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file Inter activity factor.

33. The system of claim 25 wherein generating the new sub-segment list further comprises the step of:

determining a file usage factor describing a number of requests for said data object for a period of time.

34. The system of claim 33 wherein the first function is further dependent upon the file usage factor.

35. The system of claim 34 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

36. The system of claim 33 wherein the second function is further dependent upon the file usage factor.

37. The system of claim 36 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

38. The system of claim 25 wherein generating the new sub-segment list further comprises the steps of:

determining a file usage factor describing a number of requests for said data object for a period of time; and

determining a file interactivity factor describing a number of jumps by the second computing system within the data object.

39. The system of claim 38 wherein the first function is further dependent upon the file usage factor and the file interactivity factor.

40. The system of claim 39 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H+I

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load,

H is the file usage factor, and

 

(a) I is the file Inter activity factor.

41. The system of claim 38 wherein the second function is further dependent upon the file usage factor and the file interactivity factor.

42. The system of claim 41 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data object storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

43. The system of claim 24 wherein the load balancing apparatus generates a listing of all copies of all segments of the requested data objects.

44. The system of claim 24 wherein a data object storage device having a copied segment of the requested data object is selected to transfer said data object to a requesting computing system.

45. The system of claim 24 wherein the load balancing apparatus comprises:

a presence determining device to determine the presence of all segments and sub-segments of the requested data object; and

a segment retrieving device which, if there are missing segments and sub-segments and sub-segments of the requested data object, said segment retrieving device assigns each of those missing segments and sub segments a file identification and file location, such that those missing segments are assigned to data object storage devices having the least loading, and then said segment retrieving device retrieves those missing segments from a back-up data object storage device.

46. The system of claim 24 wherein the load balancing apparatus further comprises:

a segment indicator that is set to indicate which of the segments of the data object to be transferred next; and

a current data object storage device indicator to specify initially a primary location of the segment identified by the segment indicatory;

whereby the load balancing apparatus performs the steps of;

a) determining if the loading of the data object storage device indicated by the current data object storage device indicator exceeds the maximum loading with transfer of the segment indicated by the segment indicator,

b) if said loading exceeds the maximum loading, seting the current data object storage device indicator to a next location of the segment indicated by the segment indicator, and

c) repeatedly executing steps a) and b) until said loading is not exceeded.

47. The system of claim 24 wherein transferring of the segments of the data object comprises the actions of reading said segments from the data object storage device, writing said segments to the data object storage device, and copying said segments from a said data object storage device to an alternate data object storage device, whereby said loading of the data object storage device is allocated between the reading, writing, and copying of the segments to prevent interference with said reading of the segments.

48. The system of claim 24 wherein the requested data object is a video data file to be streamed isochronously to the requesting computer system.

49. An apparatus for balancing a loading of data storage devices attached to multiple computing systems comprising:

means for acquiring a listing of locations of all segments of a requested data object including all copies of said segments and sub-segments of the requested data object;

means for evaluating the loading of the data storage devices attached to the multiple computing systems containing all copies of all segments of the requested data object;

means for selecting data storage devices containing copies of each segment of the data object having a least loading, which is less than a maximum loading for said data storage devices;

means for generating a sub-segment list for any segment of the requested data object residing on said data storage device would have a loading greater than the maximum loading if said segment of the requested data object were transferred,

means for determining a load margin for all available data storage devices;

means for assigning locations for each sub-segment on each available data storage device having the least loading;

means for assigning file names to each sub-segment,

whereby said means for generating a sub-segment list, said means for determining a load margin, said means for assigning locations for each sub-segment, and said means for assigning file names function if the loading of the data storage devices is greater than the maximum loading for said data storage devices;

means for selecting said each available data storage device containing each sub-segment; and

means for transferring those segments of said requested data object to a requesting computer system.

50. The apparatus of claim 49 wherein means for generating the new sub-segment list comprises:

means for determining a number of all available data storage devices that may retain a plurality of sub-segments of said sub-segment of the requested data object;

means for determining a maximum data object transfer load for the available data storage devices;

means for assigning a minimum sub-segment size which is the smallest amount of data to be contained within one sub-segment of the segment;

means for calculating a first sub-segment size as a first function of a number of the data storage devices, the current digital data transfer load, the maximum digital data transfer load, and the minimum sub-segment size;

means for assigning a last sub-segment size as the minimum sub-segment size;

means for calculating all remaining sub-segment sizes as a second function of the number of the data storage devices, the current digital data transfer load, the maximum data object transfer load, and the minimum sub-segment size; and

means for partitioning said segment into sub-segments whereby the first sub-segment of the segment is of the first sub-segment size, the last sub-segment of the segment is of the last sub-segment size, and all the remaining sub-segments of the segment is of the remaining sub-segment sized.

51. The apparatus of claim 50 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load, and

C_i is the current data object transfer load.

52. The apparatus of claim 51 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load, and

C_I is the current data object transfer load.

53. The apparatus of claim 50 wherein the means for the new sub-segment list further comprises:

means for determining a file interactivity factor describing a number of jumps by the second computing system within the data object.

54. The apparatus of claim 53 wherein the first function is further dependent upon the file interactivity factor.

55. The apparatus of claim 54 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(m_I/M_I−

C_I)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file interactivity factor.

56. The medium of claim 55 wherein the requested data object is a video data file to be streamed isochronously to the requesting computer system.

57. The apparatus of claim 53 wherein the second function is further dependent upon the file interactivity factor.

58. The apparatus of claim 57 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file Inter activity factor.

59. The apparatus of claim 50 wherein the means for generating the new sub-segment list further comprises the step of:

determining a file usage factor describing a number of requests for said data object for a period of time.

60. The apparatus of claim 59 wherein the first function is further dependent upon the file usage factor.

61. The apparatus of claim 60 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

62. The apparatus of claim 59 wherein the second function is further dependent upon the file usage factor.

63. The apparatus of claim 62 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

64. The apparatus of claim 50 wherein the means for generating the new sub-segment list further comprises:

means for determining a file usage factor describing a number of requests for said data object for a period of time; and

means for determining a file interactivity factor describing a number of jumps by the second computing system within the data object.

65. The apparatus of claim 64 wherein the first function is further dependent upon the file usage factor and the file interactivity factor.

66. The apparatus of claim 65 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load,

H is the file usage factor, and

I is the file Inter activity factor.

67. The apparatus of claim 64 wherein the second function is further dependent upon the file usage factor and the file interactivity factor.

68. The apparatus of claim 67 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

69. The apparatus of claim 49 further comprising:

means for determining the presence of all segments and sub-segments of the requested data object;

means for assigning each of those missing segments a file identification and file location, such that those missing segments are assigned to data storage devices having the least loading, if there are missing segments and sub-segments of the requested data object; and

means for retrieving those missing segments from a back-up data storage device.

70. The apparatus of claim 69 wherein the means for selecting the data storage devices containing copies of the segments and sub-segments of the requested data object and having the least loading comprises:

means for setting a current segment indicator to indicate which of the segments of the data object is to be transferred next;

means for setting a current data storage device indicator to specify a primary location of the segment to be transferred next;

means for incrementing the current data storage device indicator to a next location of the segment to be transferred, if the transfer of said segment causes the loading of the data storage device containing said segment to be exceeded; and

means for repeatedly activating said means for incrementing the current data storage device indicator until said loading is not exceeded.

71. The apparatus of claim 69 wherein transferring of the segments of the data object comprises the actions of reading said segments from the data storage device, writing said segments to the data storage device, and copying said segments from a said data storage device to an alternate data storage device, whereby said loading of the data storage device is allocated between the reading, writing, and copying of the segments to prevent interference with said reading of the segments.

72. The apparatus of claim 69 wherein the requested data object is a video data file to be streamed isochronously to the requesting computer system.

73. A medium for retaining a computer program which, when executed on a computing system, balances a loading of data storage devices attached to multiple computing systems, whereby said program executes the steps of:

acquiring a listing of locations of all segments of a requested data object including all copies of said segments and sub-segments of the requested data object;

evaluating the loading of the data storage devices attached to the multiple computing systems containing all copies of all segments of the requested data object;

selecting data storage devices containing copies of each segment of the requested data object having a least loading, which is less than a maximum loading for said data storage devices;

if the loading of the data storage devices is greater than the maximum loading for said data storage devices, generating a sub-segment list for any segment of the requested data object residing on said data storage device would have a loading greater than the maximum loading if said segment of the requested data object were transferred, determining a load margin for all available data storage devices, assigning locations for each sub-segment on each available data storage device having the least loading, and assigning file names to each sub-segment;

selecting said each available data storage device containing each sub-segment; and

transferring those segments of said requested data object to a requesting computer system.

74. The medium of claim 73 wherein generating the new sub-segment list comprises the steps of:

determining a number of all available data storage devices that may retain a plurality of sub-segments of said sub-segment of the requested data object;

determining a maximum data object transfer load for the available data storage devices;

assigning a minimum sub-segment size which is the smallest amount of data to be contained within one sub-segment of the segment;

calculating a first sub-segment size as a first function of a number of the data storage devices, the current digital data transfer load, the maximum digital data transfer load, and the minimum sub-segment size;

assigning a last sub-segment size as the minimum sub-segment size;

calculating all remaining sub-segment sizes as a second function of the number of the data storage devices, the current digital data transfer load, the maximum data object transfer load, and the minimum sub-segment size; and

partitioning said segment into sub-segments whereby the first sub-segment of the segment is of the first sub-segment size, the last sub-segment of the segment is of the last sub-segment size, and all the remaining sub-segments of the segment is of the remaining sub-segment sized.

75. The medium of claim 74 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load, and

C_I is the current data object transfer load.

76. The medium of claim 74 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load, and

C_I is the current data object transfer load.

77. The medium of claim 74 wherein generating the new sub-segment list further comprises the step of:

determining a file interactivity factor describing a number of jumps by the second computing system within the requested data object.

78. The medium of claim 77 wherein the first function is further dependent upon the file interactivity factor.

79. The medium of claim 78 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file interactivity factor.

80. The medium of claim 74 wherein the second function is further dependent upon the file interactivity factor.

81. The medium of claim 80 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

I is the file Inter activity factor.

82. The medium of claim 74 wherein generating the new sub-segment list further comprises the step of:

determining a file usage factor describing a number of requests for said requested data object for a period of time.

83. The medium of claim 82 wherein the first function is further dependent upon the file usage factor.

84. The medium of claim 83 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

85. The medium of claim 82 wherein the second function is further dependent upon the file usage factor.

86. The medium of claim 85 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

87. The medium of claim 74 wherein generating the new sub-segment list further comprises the steps of:

determining a file usage factor describing a number of requests for said data object for a period of time; and

determining a file interactivity factor describing a number of jumps by the second computing system within the requested data object.

88. The medium of claim 87 wherein the first function is further dependent upon the file usage factor and the file interactivity factor.

89. The medium of claim 88 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H+I

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load,

H is the file usage factor, and

I is the file Inter activity factor.

90. The medium of claim 87 wherein the second function is further dependent upon the file usage factor and the file interactivity factor.

91. The medium of claim 90 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of a segment of the requested data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the segments of the requested data object,

M_I is the maximum data object transfer load,

C_I is the current data object transfer load, and

H is the file usage factor.

92. The medium of claim 74 further comprising the steps of:

determining the presence of all segments and sub-segments of the requested data object;

if there are missing segments and sub-segments of the requested data object, assigning each of those missing segments a file identification and file location, such that those missing segments are assigned to data storage devices having the least loading; and

retrieving those missing segments from a back-up data storage device.

93. The medium of claim 92 wherein selecting the data storage devices containing copies of the segments and sub-segments of the requested data object and having the least loading comprises the steps of:

setting a current segment indicator to indicate which of the segments of the data object is to be transferred next;

setting a current data storage device indicator to specify a primary location of the segment to be transferred next;

if the transfer of said segment causes the loading of the data storage device containing said segment to be exceeded, incrementing the current data storage device indicator to a next location of the segment to be transferred; and

repeatedly incrementing the current data storage device indicator executing step G) until said loading is not exceeded.

94. The medium of claim 74 wherein transferring of the segments of the data object comprises the actions of reading said segments from the data storage device, writing said segments to the data storage device, and copying said segments from a said data storage device to an alternate data storage device, whereby said loading of the data storage device is allocated between the reading, writing, and copying of the segments to prevent interference with said reading of the segments.

95. A method for balancing a loading of data storage devices containing video data objects attached to multiple computing systems comprising the steps of:

acquiring a listing of locations of all segments of a requested video data object including all copies of said segments of the requested video data object;

evaluating the loading of the data storage devices attached to the multiple computing systems containing all copies of all segments of the reqested video data object;

selecting data storage devices containing copies of each segment of the video data object having a least loading, which is less than a maximum loading for said data storage devices;

if the loading of the data storage devices is greater than the maximum loading for said data storage devices, generating a sub-segment list for any segment of the requested video data object residing on said data storage device would have a loading greater than the maximum loading if said segment of the requested video data object were transferred, determining a load margin for all available data storage devices, assigning locations for each sub-segment on each available data storage device having the least loading, and assigning file names to each sub-segment;

selecting said each available data storage device containing each sub-segment; and

transferring those segments of said requested video data object to a requesting computer system.

96. The method of claim 95 wherein generating the new sub-segment list comprises the steps of:

determining a number of all available data storage devices that may retain a plurality of sub-segments of said sub-segment of the requested video data object;

determining a maximum video data object transfer load for the available data storage devices;

assigning a minimum sub-segment size which is the smallest amount of data to be contained within one sub-segment of the segment;

calculating a first sub-segment size as a first function of a number of the data storage devices, the current digital data transfer load, the maximum digital data transfer load, and the minimum sub-segment size;

assigning a last sub-segment size as the minimum sub-segment size;

calculating all remaining sub-segment sizes as a second function of the number of the data storage devices, the current digital data transfer load, the maximum video data object transfer load, and the minimum sub-segment size; and

partitioning said segment into sub-segments whereby the first sub-segment of the segment is of the first sub-segment size, the last sub-segment of the segment is of the last sub-segment size, and all the remaining sub-segments of the segment is of the remaining sub-segment sized.

97. The method of claim 96 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load, and

C_I is the current video data object transfer load.

98. The method of claim 96 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load, and

C_I is the current video data object transfer load.

99. The method of claim 96 wherein generating the new sub-segment list further comprises the step of:

determining a file interactivity factor describing a number of jumps by the second computing system within the video data object.

100. The method of claim 99 wherein the first function is further dependent upon the file interactivity factor.

101. The method of claim 100 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

I is the file interactivity factor.

102. The method of claim 99 wherein the second function is further dependent upon the file interactivity factor.

103. The method of claim 102 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

I is the file Inter activity factor.

104. The method of claim 96 wherein generating the new sub-segment list further comprises the step of:

determining a file usage factor describing a number of requests for said video data object for a period of time.

105. The method of claim 104 wherein the first function is further dependent upon the file usage factor.

106. The method of claim 105 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

H is the file usage factor.

107. The method of claim 104 wherein the second function is further dependent upon the file usage factor.

108. The method of claim 107 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

H is the file usage factor.

109. The method of claim 96 wherein generating the new sub-segment list further comprises the steps of:

determining a file usage factor describing a number of requests for said video data object for a period of time; and

determining a file interactivity factor describing a number of jumps by the second computing system within the video data object.

110. The method of claim 109 wherein the first function is further dependent upon the file usage factor and the file interactivity factor.

111. The method of claim 110 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H+I

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load,

H is the file usage factor, and

I is the file Inter activity factor.

112. The method of claim 109 wherein the second function is further dependent upon the file usage factor and the file interactivity factor.

113. The method of claim 112 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of data storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

H is the file usage factor.

114. The method of claim 96 further comprising the steps of:

determining the presence of all segments of the requested video data object;

if there are missing segments of the requested video data object, assigning each of those missing segments a file identification and file location, such that those missing segments are assigned to data storage devices having the least loading; and

retrieving those missing segments from a back-up data storage device.

115. The method of claim 96 wherein selecting the data storage devices containing copies of the segments of the requested video data object and having the least loading comprises the steps of:

setting a current segment indicator to indicate which of the segments of the video data object is to be transferred next;

setting a current data storage device indicator to specify a primary location of the segment to be transferred next;

if the transfer of said segment causes the loading of the data storage device containing said segment to be exceeded, incrementing the current data storage device indicator to a next location of the segment to be transferred; and

repeatedly incrementing the current data storage device indicator until said loading is not exceeded.

116. The method of claim 96 wherein transferring of the segments of the video data object comprises the actions of reading said segments from the data storage device, writing said segments to the data storage device, and copying said segments from a said data storage device to an alternate data storage device, whereby said loading of the data storage device is allocated between the reading, writing, and copying of the segments to prevent interference with said reading of the segments.

117. The method of claim 96 wherein the requested video data object is streamed isochronously to the requesting computer system.

118. A video data object service system in communication with a plurality of computing systems to provide at least one video data object of plurality of video data object to at least one of the plurality of computing system, comprising:

a plurality of video data object storage devices in communication with each other and with any of the plurality of computing systems; and

a load balancing apparatus in communication with the plurality of video data object storage devices to balance a loading of said video data object storage devices during transfer of said video data objects,

said load balancing apparatus comprising;

a load evaluator to assess the loading of the video data object storage devices containing segments of said video data objects,

a video data object storage device selector to create a selection list to indicate selection of those video data object storage devices containing copies of each segment of a requested video data object having the least loading, and

a copying initiator to initiate a copying and further segmenting of a segment of the video data object to an alternate video data object storage devices having low loading if all video data object storage devices containing said segment have a loading greater than a maximum loading, whereby said copying initiator generates a sub-segment list for any segment of the requested video data object residing on said video data object storage device that would have a loading greater than the maximum loading if said segment of the requested video data object were transferred, determines a load margin for all available video data object storage devices, assigns locations for each sub-segment on each available video data object storage device having the least loading, and assigns file names to each sub-segment.

119. The system of claim 118 wherein generating the new sub-segment list comprises the steps of:

determining a number of all available video data object storage devices that may retain a plurality of sub-segments of said sub-segment of the requested video data object;

determining a maximum video data object transfer load for the available video data object storage devices;

assigning a minimum sub-segment size which is the smallest amount of data to be contained within one sub-segment of the segment;

calculating a first sub-segment size as a first function of a number of the video data object storage devices, the current digital data transfer load, the maximum digital data transfer load, and the minimum sub-segment size;

assigning a last sub-segment size as the minimum sub-segment size;

calculating all remaining sub-segment sizes as a second function of the number of the video data object storage devices, the current digital data transfer load, the maximum video data object transfer load, and the minimum sub-segment size; and

partitioning said segment into sub-segments whereby the first sub-segment of the segment is of the first sub-segment size, the last sub-segment of the segment is of the last sub-segment size, and all the remaining sub-segments of the segment is of the remaining sub-segment sized.

120. The system of claim 119 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load, and

C_I is the current video data object transfer load.

121. The system of claim 119 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_i is the maximum video data object transfer load, and

C_I is the current video data object transfer load.

122. The system of claim 119 wherein generating the new sub-segment list further comprises the step of:

determining a file interactivity factor describing a number of jumps by the second computing system within the video data object.

123. The system of claim 122 wherein the first function is further dependent upon the file interactivity factor.

124. The system of claim 123 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+I

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

I is the file interactivity factor.

125. The system of claim 122 wherein the second function is further dependent upon the file interactivity factor.

126. The system of claim 125 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d(M_I/M_I−

C_I)+I

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

I is the file Inter activity factor.

127. The system of claim 119 wherein generating the new sub-segment list further comprises the step of:

determining a file usage factor describing a number of requests for said video data object for a period of time.

128. The system of claim 127 wherein the first function is further dependent upon the file usage factor.

129. The system of claim 128 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

H is the file usage factor.

130. The system of claim 127 wherein the second function is further dependent upon the file usage factor.

131. The system of claim 130 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

H is the file usage factor.

132. The system of claim 119 wherein generating the new sub-segment list further comprises the steps of:

determining a file usage factor describing a number of requests for said video data object for a period of time; and

determining a file interactivity factor describing a number of jumps by the second computing system within the video data object.

133. The system of claim 132 wherein the first function is further dependent upon the file usage factor and the file interactivity factor.

134. The system of claim 133 wherein the first function to determine the first sub-segment size is:

SubSeg1=min(SubSegSize_min, V/f)

where

SubSeg1 is the first sub-segment size,

min is the minimum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H+I

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load,

H is the file usage factor, and

I is the file Inter activity factor.

135. The system of claim 132 wherein the second function is further dependent upon the file usage factor and the file interactivity factor.

136. The system of claim 135 wherein the second function to determine the remaining sub-segment sizes is:

SubSegn=max(SubSegSize_min, V/f)

where

SubSegn is the a sub-segment size for one sub-segment of the remaining sub-segments,

max is the maximum function of two variables,

V is a total size of the video data object, and

f is determined by the formula;

f=N_d+(M_I/M_I−

C_I)+H

where

N_d is the number of video data object storage devices available to retain the sub-segments of the video data object,

M_I is the maximum video data object transfer load,

C_I is the current video data object transfer load, and

H is the file usage factor.

137. The system of claim 118 wherein the load balancing apparatus generates a listing of all copies of all segments of the requested video data objects.

138. The system of claim 118 wherein one video data object storage device having a copied segment of the requested video data object is selected to transfer said video data object to a requesting computing system.

139. The system of claim 118 wherein the load balancing apparatus comprises:

a presence determining device to determine the presence of all segments of the requested video data object; and

a segment retrieving device which, if there are missing segments of the requested video data object, said segment retrieving device assigns each of those missing segments a file identification and file location, such that those missing segments are assigned to video data object storage devices having the least loading, and then said segment retrieving device retrieves those missing segments from a back-up video data object storage device.

140. The system of claim 118 wherein the load balancing apparatus further comprises:

a segment indicator that is set to indicate which of the segments of the video data object to be transferred next; and

a current video data object storage device indicator to specify initially a primary location of the segment identified by the segment indicatory;

whereby the load balancing apparatus performs the steps of;

a) determining if the loading of the video data object storage device indicated by the current video data object storage device indicator exceeds the maximum loading with transfer of the segment indicated by the segment indicator,

b) if said loading exceeds the maximum loading, setting the current video data object storage device indicator to a next location of the segment indicated by the segment indicator, and

c) repeatedly executing steps a) and b) until said loading is not exceeded.

141. The system of claim 118 wherein transferring of the segments of the video data object comprises the actions of reading said segments from the video data object storage device, writing said segments to the video data object storage device, and copying said segments from a said video data object storage device to an alternate video data object storage device, whereby said loading of the video data object storage device is allocated between the reading, writing, and copying of the segments to prevent interference with said reading of the segments.

142. The system of claim 118 wherein the requested video data object is streamed isochronously to the requesting computer system.