Computer system and process for transferring multiple high bandwidth streams of data between multiple storage units and multiple applications in a scalable and reliable manner

• US 8,478,957 B2
• Filed: 03/19/2012
• Issued: 07/02/2013
• Est. Priority Date: 12/24/1997
• Status: Expired due to Fees

• Current Assignee: Avid Technology Incorporated
• Original Assignee: Avid Technology Incorporated
• Inventors: Peters, Eric C., Rabinowitz, Stanley, Jacobs, Herbert R., Fasciano, Peter J.
• Primary Examiner(s): BATAILLE, PIERRE MICHE
• Application Number:
  US13/423,778
• Publication Number:
  US 20120239892A1
• Time in Patent Office: 470 Days
• Field of Search: 711/112, 711/114, 711/162, 711/163, 711/165, 711/170, 711/111, 711/E12.001, 714/7, 714/6, 714/5, 714/4
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/1662 the resynchronized component or unit being a persistent storage device re-synchronization of failed mirror storage G06F11/2082; rebuild or reconstruction of parity RAID storage G06F11/1008
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 11/2097 maintaining the standby controller/processing unit updated initialisation or re-synchronisation thereof G06F11/1658 and subgroups
• CPC Class Codes: G06F 16/182 Distributed file systems
• CPC Class Codes: G06F 16/184 implemented as replicated file system
• CPC Class Codes: G06F 16/1844 Management specifically adapted to replicated file systems
• CPC Class Codes: G06F 16/70 of video data
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1029 using data related to the state of servers by a load balancer
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services
• CPC Class Codes: H04N 21/2182 involving memory arrays, e.g. RAID disk arrays RAID arrays per se G06F3/0689; use of parity to protect data in RAID systems G06F11/1008
• 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 21/2315 using interleaving
• CPC Class Codes: H04N 21/232 : Content retrieval operation locally within server, e.g. reading video streams from disk arrays storage management G06F3/0604; details of querying and searching of video data from a database G06F16/739
• CPC Class Codes: H04N 21/2393 : involving handling client requests scheduling or organising the servicing of application requests H04L67/60
• CPC Class Codes: H04N 21/2396 : characterized by admission policies admission control, resource allocation in open networks H04L12/5692; arrangements for network security using user profiles for access control H04L63/102; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/2405 : Monitoring of the internal components or processes of the server, e.g. server load allocation of resources in multiprogramming arrangements G06F9/50; performance measurement of computer activity G06F11/34
• CPC Class Codes: H04N 21/241 : Operating system [OS] processes, e.g. server setup
• CPC Class Codes: H04N 21/262 : Content or additional data distribution scheduling, e.g. sending additional data at off-peak times, updating software modules, calculating the carousel transmission frequency, delaying a video stream transmission, generating play-lists scheduling strategies for dispatcher in multiprogramming arrangements G06F9/4881; arrangements for scheduling broadcast services or broadcast-related services H04H60/06; flow control in packet networks H04L47/10; establishing a time schedule or organising the servicing of application requests H04L67/62
• CPC Class Codes: H04N 21/44004 : involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/442 : Monitoring of processes or resources, e.g. detecting the failure of a recording device, monitoring the downstream bandwidth, the number of times a movie has been viewed, the storage space available from the internal hard disk arrangements for monitoring broadcast services or broadcast-related services H04H60/29; arrangements for identifying or recognising characteristics with a direct linkage to broadcast information H04H60/35; monitoring of user activities for profile generation for accessing a video database G06F16/739; monitoring in wireless networks H04W24/00
• 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: H04N 7/17336 : Handling of requests in head-ends
• CPC Class Codes: Y10S 707/99953 : Recoverability
• CPC Class Codes: Y10S 707/99956 : File allocation

Abstract

Multiple applications request data from multiple storage units over a computer network. The data is divided into segments and each segment is distributed randomly on one of several storage units, independent of the storage units on which other segments of the media data are stored. At least one additional copy of each segment also is distributed randomly over the storage units, such that each segment is stored on at least two storage units. When an application requests a selected segment of data, the request is processed by the storage unit with the shortest queue of requests. Random fluctuations in the load applied by multiple applications on multiple storage units are balanced nearly equally over all storage units. These techniques result in a system which can transfer multiple, independent high-bandwidth streams of data in a scalable and reliable manner in both directions between multiple applications and multiple storage units.

Claims

1. A data storage system, comprising:

a plurality of client systems, each client system having a file system through which applications executed on the client system access data stored in files of the file system;

a plurality of independent storage servers, each server storing data from files of the file system;

a computer network interconnecting the plurality of independent storage servers and the plurality of client systems;

wherein each file stored on the plurality of independent storage servers is divided into segments, with two or more copies of each segment being distributed among the plurality of independent storage servers, such that each segment is stored on at least two of the storage servers;

storage maintaining information indicating the storage servers on which the segments of files are stored;

at least one of the client systems being configured to;

access, before reading data from a file, the storage to obtain the information indicating the storage servers on which the segments of the file are stored, and

communicate directly with the storage servers to request the segments of the file using the accessed information;

wherein, after writing data to a file, the information indicating the storage servers on which segments of the file are stored is updated in the storage; and

wherein, if a storage server is unavailable, segments of files stored on the unavailable storage server are copied from other storage servers that store the segments of files to other available storage servers.

2. The data storage system of claim 1, wherein at least one of the client systems is configured to:

detect when a storage server becomes unavailable;

access the storage to obtain information identifying segments stored on the unavailable storage server;

access the storage to obtain information indicating other storage servers on which the identified segments are stored;

distribute copies of the identified segments from the other storage servers among the plurality of independent storage servers that remain available, such that each segment is again stored on at least two of the storage servers that remain available.

3. The data storage system of claim 2, wherein each storage server operates independently of the other storage servers in responding to requests to read and write data on the storage server.

4. The data storage system of claim 1, wherein each storage server operates independently of the other storage servers in responding to requests to read and write data on the storage server.

5. The data storage system of claim 1, further comprising a storage management system that monitors availability of the storage servers, and, after detection of one of the storage servers as unavailable, initiates recovery of segments of files stored on the unavailable storage server.

6. The data storage system of claim 5, wherein the storage management system identifies other storage servers that store the segments of the files stored on the unavailable storage server and causes the segments to be copied from other storage servers to other available storage servers.

7. The data storage system of claim 1, further comprising a storage management system that, after notification that one of the storage servers is unavailable, initiates recovery of segments of files stored on the unavailable storage server.

8. The data storage system of claim 7, wherein the storage management system identifies other storage servers that store the segments of the files stored on the unavailable storage server and causes the segments to be copied from other storage servers to other available storage servers.

9. The data storage system of claim 1, wherein copying of segments to other available storage servers occurs while client systems access data stored in files on the storage servers in the data storage system.

10. The data storage system of claim 1, wherein segments of files stored on the unavailable storage server are copied in priority order according to priority of the files in which the segments are stored.

11. The data storage system of claim 1, wherein instructions to copy a segment are subordinated to file service requests from client systems.

12. A data storage system, comprising:

a plurality of client systems, each client system having a file system through which applications executed on the client system access data stored in files of the file system;

a plurality of independent storage servers, each server storing data from files of the file system;

a computer network interconnecting the plurality of independent storage servers and the plurality of client systems;

wherein each file stored on the plurality of independent storage servers is divided into segments, with two or more copies of each segment being distributed among the plurality of independent storage servers, such that each segment is stored on at least two of the storage servers;

storage maintaining information indicating the storage servers on which the segments of files are stored;

at least one of the client systems being configured to;

access, before reading data from a file, the storage to obtain the information indicating the storage servers on which the segments of the file are stored, and

communicate directly with the storage servers to request the segments of the file using the accessed information;

wherein, after writing data to a file, the information indicating the storage servers on which segments of the file are stored is updated in the storage; and

wherein, after an additional storage server becomes available in the plurality of independent storage servers, each file that is newly stored on the plurality of independent storage servers is divided into segments, with two or more copies of each segment being distributed among the plurality of independent storage servers including the additional storage server, such that each segment is stored on at least two of the storage servers.

13. The data storage server of claim 12, further comprising a storage management system that monitors availability of the storage servers, and, after detection of an additional storage server becoming available, initiates redistribution of segments of files stored on the storage servers so as to distribute segments of files on the additional storage server.

14. The data storage system of claim 13, wherein the storage management system identifies storage servers that store segments of a file, and causes segments to be copied from the identified storage servers to the additional storage server.

15. The data storage server of claim 12, further comprising a storage management system, that after notification of availability of an additional storage server, initiates redistribution of segments of files stored on the storage servers so as to distribute segments of files on the additional storage server.

16. The data storage system of claim 15, wherein the storage management system identifies storage servers that store segments of a file, and causes segments to be copied from the identified storage servers to the additional storage server.

17. The data storage system of claim 12, wherein at least one of the client systems is configured to:

identify when an additional storage server becomes available;

identify segments to be redistributed to the additional storage server;

access the storage to obtain information indicating storage servers on which the identified segments are stored;

cause the identified segments to be copied from the other storage servers to the additional storage server; and

update the information in the storage indicating the storage servers on which the identified segments are stored.

18. The data storage system of claim 17, wherein redistribution of the identified segments occurs while client systems access data stored in files on the storage servers in the data storage system.

19. The data storage system of claim 17, wherein instructions to copy a segment are subordinated to file service requests from client systems.

20. The data storage system of claim 12, wherein the additional storage unit is configured to:

start operation;

inform client systems that operation has started; and

establish processes to respond to requests from client systems.

21. A data storage system, comprising:

a plurality of client systems, each client system having a file system through which applications executed on the client system access data stored in files of the file system;

a plurality of independent storage servers, each server storing data from files of the file system;

a computer network interconnecting the plurality of independent storage servers and the plurality of client systems;

wherein each file stored on the plurality of independent storage servers is divided into segments, with two or more copies of each segment being distributed among the plurality of independent storage servers, such that each segment is stored on at least two of the storage servers;

storage maintaining information indicating the storage servers on which the segments of files are stored;

at least one of the client systems being configured to;

access, before reading data from a file, the storage to obtain the information indicating the storage servers on which the segments of the file are stored, and

communicate directly with the storage servers to request the segments of the file using the accessed information;

wherein, after writing data to a file, the information indicating the storage servers on which segments of the file are stored is updated in the storage; and

a storage management system configured to cause an additional copy of segments of a file to be distributed among the plurality of independent storage servers and to update the information indicating the storage servers on which segments of the file are stored.

22. The data storage system of claim 21 wherein the copy of each segment is processed separately and asynchronously from the copies of the other segments.

23. A data storage system, comprising:

a plurality of client systems, each client system having a file system through which applications executed on the client system access data stored in files of the file system;

a plurality of independent storage servers, each server storing data from files of the file system;

a computer network interconnecting the plurality of independent storage servers and the plurality of client systems;

wherein each file stored on the plurality of independent storage servers is divided into segments, with two or more copies of each segment being distributed among the plurality of independent storage servers;

such that each segment is stored on at least two of the storage servers, wherein the copy of each segment is processed separately and asynchronously from the copies of the other segments;

storage maintaining information indicating the storage servers on which the segments of files are stored;

at least one of the client systems being configured to;

access, before reading data from a file, the storage to obtain the information indicating the storage servers on which the segments of the file are stored, and

communicate directly with the storage servers to request the segments of the file using the accessed information;

wherein, after writing data to a file, the information indicating the storage servers on which segments of the file are stored is updated in the storage.