Abstract: Various embodiments of a system and method for backing up a plurality of copies of a file are described. A first copy of the file may be owned by a first user, and a second copy of the file may be owned by a second user. The file is split into a plurality of segments, and each segment is encrypted with a respective segment key. Each encrypted segment is transmitted to and stored on a server computer system. De-duplication techniques are used to ensure that only a single instance of each encrypted segment is stored. The segment keys used to encrypt the file segments are also stored on the server computer system in an encrypted form. De-duplication techniques may be utilized so that only a single instance of the encrypted segment keys is stored.

Abstract: A distributed object storage system has a monitoring agent and/or a maintenance agent configured to determine for each of a plurality of repair tasks the actual concurrent failure tolerance of a corresponding repair data object. The actual concurrent failure tolerance corresponds to the number of storage elements that store sub blocks of the repair data object and are allowed to fail concurrently.

Abstract: A method and computer device for storage and retrieval of a data object on a storage medium. The method includes steps of disassembling the data object into a predetermined number of redundant sub blocks, storing the redundant sub blocks on the storage medium, retrieving at least a predetermined multiple of a minimal spreading requirement of the redundant sub blocks from the storage medium, and assembling the data object from any combination of a particular number of the redundant sub blocks, the particular number corresponding to a predetermined multiple of a minimal spreading requirement. The computer device includes modules for performing the steps.

Abstract: A method and computer device for storage and retrieval of a data object on a storage medium. The method includes steps of disassembling the data object into a predetermined number of redundant sub blocks, storing the redundant sub blocks on the storage medium, retrieving at least a predetermined multiple of a minimal spreading requirement of the redundant sub blocks from the storage medium, and assembling the data object from any combination of a particular number of the redundant sub blocks, the particular number corresponding to a predetermined multiple of a minimal spreading requirement. The computer device includes modules for performing the steps.

Abstract: Various methods and systems for using adaptive data compression in a backup system are disclosed. One method involves detecting whether to compress a unit of storage that is to be backed up. The detecting involves attempting to compress a portion of the unit of storage. If the attempt to compress the portion of the unit of storage meets a specified compression performance threshold, i.e., if the unit of storage is compressible, the unit of storage is compressed. Otherwise the unit of storage is not compressed.

Abstract: Analyzing backup objects maintained by a de-duplication server. A plurality of first objects may be maintained. Each first object may refer to second object(s) and each second object may refer back to at least one first object. For each respective first object, the respective first object may be analyzed to determine the one or more second objects referred to by the respective first object. Correspondingly, a command may be generated for each respective second object of the determined second object(s), thereby generating a plurality of commands. Each command may be used to verify that the respective second object refers back to the respective first object. The plurality of commands may be sorted into a disk access order. The commands may be used to verify that each second object refers back to first objects that refer to the second object.

Abstract: A distributed object storage system includes several performance optimizations with respect to storing very small data objects, very large data objects and CRC calculations.

Abstract: A method and computer device for storage and retrieval of a data object on a storage medium. The method includes steps of disassembling the data object into a predetermined number of redundant sub blocks, storing the redundant sub blocks on the storage medium, retrieving at least a predetermined multiple of a minimal spreading requirement of the redundant sub blocks from the storage medium, and assembling the data object from any combination of a particular number of the redundant sub blocks, the particular number corresponding to a predetermined multiple of a minimal spreading requirement. The computer device includes modules for performing the steps.

Abstract: A distributed object storage system has a monitoring agent and/or a maintenance agent configured to determine for each of a plurality of repair tasks the actual concurrent failure tolerance of a corresponding repair data object. The actual concurrent failure tolerance corresponds to the number of storage elements that store sub blocks of the repair data object and are allowed to fail concurrently.

Abstract: A distributed object storage system includes several performance optimizations with respect to storing very small data objects, very large data objects and CRC calculations.

Abstract: The invention concerns a distributed object storage system (1) that comprises a spreading module (410) which makes a selection of a number of storage elements (300) being larger or equal to a desired spreading width by means of a spreading policy that comprises rules for selecting storage elements (300) in function of a first hierarchy level identifier (70.1) and/or a second hierarchy level identifier (70.2).

Abstract: A computer-implemented method for data-selection-specific data deduplication associated with a single-instance-storage computing subsystem may comprise: 1) detecting a request to store a data selection to the single-instance-storage computing subsystem, 2) identifying a data-selection-specific fingerprint set associated with the data selection and stored on a storage device, and 3) utilizing the data-selection-specific fingerprint set associated with the data selection for data deduplication associated with the request to store the data selection to the single-instance-storage computing subsystem. Other exemplary data deduplication methods, as well as corresponding exemplary systems and computer-readable media, are also disclosed.

Abstract: The invention concerns a distributed object storage system (1) comprising a maintenance agent (740) instructing an encoding module (400) to disassemble a repair data object into a specific number of repair sub blocks, this specific number being equal to or greater than said number of missing sub blocks and less then the predetermined number of sub blocks during a regular storage operation.

Abstract: The invention concerns a distributed object storage system (1) comprising a maintenance agent (740) instructing an encoding module (400) to disassemble a repair data object into a specific number of repair sub blocks, this specific number being equal to or greater than said number of missing sub blocks and less then the predetermined number of sub blocks during a regular storage operation.

Abstract: The invention concerns a distributed object storage system (1) that comprises a spreading module (410) which makes a selection of a number of storage elements (300) being larger or equal to a desired spreading width by means of a spreading policy that comprises rules for selecting storage elements (300) in function of a first hierarchy level identifier (70.1) and/or a second hierarchy level identifier (70.2).

Abstract: A computer-implemented method for seeding a fingerprint cache for data deduplication associated with a single-instance-storage computing subsystem may comprise: 1) maintaining server-side fingerprint usage data for a plurality of fingerprints associated with data stored in the single-instance-storage computing subsystem and 2) building, based at least in part on the fingerprint usage data, a server-side fingerprint cache for use in client-side data deduplication, the server-side fingerprint cache comprising at least a subset of the plurality of fingerprints. The method may further comprise: 1) receiving a request for the server-side fingerprint cache from a client-side data deduplication computing subsystem and 2) transmitting data representative of the server-side fingerprint cache to the client-side data deduplication computing subsystem for use in client-side data deduplication associated with the single-instance-storage computing subsystem.

Abstract: A computer-implemented method for controlling initialization of a fingerprint cache for data deduplication associated with a single-instance-storage computing subsystem may comprise: 1) detecting a request to store a data selection to the single-instance-storage computing subsystem, 2) leveraging a client-side fingerprint cache associated with a previous storage of the data selection to the single-instance-storage computing subsystem to initialize a new client-side fingerprint cache, and 3) utilizing the new client-side fingerprint cache for data deduplication associated with the request to store the data selection to the single-instance-storage computing subsystem. Other exemplary methods of controlling initialization of a fingerprint cache for data deduplication, as well as corresponding exemplary systems and computer-readable-storage media, are also disclosed.

Abstract: Analyzing backup objects maintained by a de-duplication server. A plurality of first objects may be maintained. Each first object may refer to second object(s) and each second object may refer back to at least one first object. For each respective first object, the respective first object may be analyzed to determine the one or more second objects referred to by the respective first object. Correspondingly, a command may be generated for each respective second object of the determined second object(s), thereby generating a plurality of commands. Each command may be used to verify that the respective second object refers back to the respective first object. The plurality of commands may be sorted into a disk access order. The commands may be used to verify that each second object refers back to first objects that refer to the second object.

Abstract: A computer-implemented method for controlling initialization of a fingerprint cache for data deduplication associated with a single-instance-storage computing subsystem may comprise: 1) detecting a request to store a data selection to the single-instance-storage computing subsystem, 2) leveraging a client-side fingerprint cache associated with a previous storage of the data selection to the single-instance-storage computing subsystem to initialize a new client-side fingerprint cache, and 3) utilizing the new client-side fingerprint cache for data deduplication associated with the request to store the data selection to the single-instance-storage computing subsystem. Other exemplary methods of controlling initialization of a fingerprint cache for data deduplication, as well as corresponding exemplary systems and computer-readable-storage media, are also disclosed.

Abstract: There can be provided a system, method and apparatus to enable a data object to be removed from a single-instancing data object store in such a way as to ensure that only data objects to which all references have been removed are actually removed from the store. Thereby, consistency and reliability of storage can be maintained while allowing a data object which genuinely needs to be deleted to be removed from the store.