Abstract: Access to objects of a computing environment is managed. Access to an object of the computing environment is prohibited via one cached entity corresponding to the object, while access to the object is allowed via another cached entity. The cached entities are concurrently maintained for a period of time, but the one cached entity is in a shadow state. In one example, the cached entities are session locks and the object is a file system object.

Abstract: Provided are a method, system, and article of manufacture for applying a policy criteria to files in a backup image. A backup image of files in a file system is maintained. A policy is applied to the files in the backup image to determine files satisfying a policy criteria. A list is prepared indicating the determined files. The determined files in the file system are accessed and a deferred operation indicated in the applied policy is applied to the accessed files in the file system.

Abstract: Transitioning a data file in an archive system from read-write to write-once-read-many (“WORM”) is triggered by a control file rather than using a timeout approach or a overload approach. A storage manager may receive a series of archive instructions to write a data file to an archive. During this time, the archive file may be in a read-write state. The storage manager may receive a control file, which may be structured, such as an XML file. Receipt of the control file signals to an storage manager archive system that the data file has been written to the archive and triggers the storage manager to make the data file immutable by switching it from read-write state to WORM state.

Abstract: Transitioning a data file in an archive system from read-write to write-once-read-many (“WORM”) is triggered by a control file rather than using a timeout approach or a overload approach. A storage manager may receive a series of archive instructions to write a data file to an archive. During this time, the archive file may be in a read-write state. The storage manager may receive a control file, which may be structured, such as an XML file. Receipt of the control file signals to an storage manager archive system that the data file has been written to the archive and triggers the storage manager to make the data file immutable by switching it from read-write state to WORM state.

Abstract: Access to objects of a computing environment is managed. Access to an object of the computing environment is prohibited via one cached entity corresponding to the object, while access to the object is allowed via another cached entity. The cached entities are concurrently maintained for a period of time, but the one cached entity is in a shadow state. In one example, the cached entities are session locks and the object is a file system object.

Abstract: Access to objects of a computing environment is managed. Access to an object of the computing environment is prohibited via one cached entity corresponding to the object, while access to the object is allowed via another cached entity. The cached entities are concurrently maintained for a period of time, but the one cached entity is in a shadow state. In one example, the cached entities are session locks and the object is a file system object.

Abstract: A system and method for managing logical versions of a filesystem made through a near-instantaneous copy process is provided. Each logical version of the filesystem, including the primary version, is assigned a unique epoch number or other identifying value, and each filesystem object is assigned two epoch numbers that define the space of logical versions for which the object exists. A list of all valid epoch numbers are maintained in a version table. The near-instantaneous creation of a logical version of the filesystem requires inserting a unique epoch number entry in the version table (106) and the next epoch number to the new logical version. An original state of the system is preserved through the use of a copy-on-write procedure for filesystem objects that are reference by that logical filesystem version (120). Accordingly, filesystem versions are maintained and original states of previous states of the logical filesystem versions are preserved.

Abstract: A method and system for asserting a lock in a distributed file system is provided. All distributed locks have a lease for a limited time period, wherein the lease may be renewed periodically. A lock manager data structure is provided to maintain mode compatibility of locks granted to different client nodes for the same object. The process of acquiring or reasserting a lock includes determining whether there are other valid locks in use, as well as whether a valid lock is in operation in a conflicting or compatible mode with a requested lock. A new lock lease may be granted and a lock lease which has expired may be reasserted if a conflicting lease is not present.

Abstract: Various copy-on-write implementations for a computing environment are presented. One copy-on-write implementation includes employing a read mapping table to perform a first virtual block to physical block mapping for use in reading a block of data of a file to be copy-on-written from physical storage for modification; and employing a different, write mapping table to perform a second virtual block to physical block mapping for use in writing a modified block of the file data to physical storage, wherein copy-on-write of the block of data is achieved using a single write operation. In another implementation, a distributed copy-on-write of a file for a client server environment is presented. This distributed copy-on-write includes performing, by a first client, copy-on-write of at least one block of data of the file to be copy-on-written, and performing, by a second client, copy-on-write of at least one other block of data of the file, wherein multiple clients perform the copy-on-write of the file.

Abstract: Various copy-on-write implementations for a computing environment are presented. One copy-on-write implementation includes employing a read mapping table to perform a first virtual block to physical block mapping for use in reading a block of data of a file to be copy-on-written from physical storage for modification; and employing a different, write mapping table to perform a second virtual block to physical block mapping for use in writing a modified block of the file data to physical storage, wherein copy-on-write of the block of data is achieved using a single write operation. In another implementation, a distributed copy-on-write of a file for a client server environment is presented. This distributed copy-on-write includes performing, by a first client, copy-on-write of at least one block of data of the file to be copy-on-written, and performing, by a second client, copy-on-write of at least one other block of data of the file, wherein multiple clients perform the copy-on-write of the file.

Abstract: Access to objects of a computing environment is managed. Access to an object of the computing environment is prohibited via one cached entity corresponding to the object, while access to the object is allowed via another cached entity. The cached entities are concurrently maintained for a period of time, but the one cached entity is in a shadow state. In one example, the cached entities are session locks and the object is a file system object.

Abstract: A method and system for asserting a lock in a distributed file system is provided. All distributed locks have a lease for a limited time period, wherein the lease may be renewed periodically. A lock manager data structure is provided to maintain mode compatibility of locks granted to different client nodes for the same system object. The process of acquiring (60) or reasserting (140) a lock includes determining whether there are other valid locks in use, as well as whether a valid lock is operation in a conflicting or compatible mode with a requested lock (86, 166). A new lock lease maybe granted (120) and a lock lease which has expired may be reasserted (172) if a conflicting lease is not present.

Abstract: A system and method for managing logical versions of a filesystem made through a near-instantaneous copy process is provided. Each logical version of the filesystem, including the primary version, is assigned a unique epoch number or other identifying value, and each filesystem object is assigned two epoch numbers that define the space of logical versions for which the object exists. A list of all valid epoch numbers are maintained in a version table. The near-instantaneous creation of a logical version of the filesystem requires inserting a unique epoch number entry in the version table (106) and the next epoch number to the new logical version. An original state of the system is preserved through the use of a copy-on-write procedure for filesystem objects that are reference by that logical filesystem version (120). Accordingly, filesystem versions are maintained and original states of previous states of the logical filesystem versions are preserved.

Abstract: This invention provides a one-pass storage process to manage storage space in a storage hierarchy system wherein whole objects or fragments of whole objects can be retrieved efficiently. Metadata to represent appropriate geometric characteristics of storage devices, units of transfer to minimize retrieval time, and buffers, are used to control the storage allocation. A plurality of objects from an object set are aggregated into at least one object grouping for storage where the object grouping is smaller than a minimum storage size. For each object grouping and each object not in an object grouping, a determination is made of the total number of blocks of storage needed and a minimum transfer size. Extents of blocks are identified in the storage device of a size greater than the minimum transfer size totalling the total number of blocks of storage needed.

Abstract: A system and method are provided for preserving spacial and temporal locality of sets of related objects when moving the sets within a storage hierarchy via a common server. The appropriate meta data is gathered to track the spacial and temporal locality of the sets of objects being moved within the storage hierarchy and the algorithm uses the meta data to preserve the spacial and temporal locality when moving the objects. A collection of logically clustered data objects is identified. The logical cluster is then moved down through the storage hierarchy together to be stored in less costly storage devices. The logical cluster of data objects is then retrievable more efficiently as a whole when requested.