Abstract: A storage system according to one embodiment includes logic integrated with and/or executable by a hardware processor, the logic being configured to: determine an ownership status for each of a plurality of instances of a file in a first storage tier and in a second storage tier of the storage system; determine locations of the instances of the file in the storage system; determine whether the instances of the file in the first storage tier are being accessed or not being accessed; and assign each of the instances of the file to one of a plurality of indices using the determined ownership status, location, and whether the instances are being accessed.

Abstract: A storage system, according to one embodiment, includes a processor and logic integrated with and/or executable by the processor. The logic is configured to: search for an instance of a file or portion thereof on a second storage tier; at least one of: associate the instance of the file or portion thereof on the second storage tier with a first user when the instance of the file or portion thereof is not associated with any user, and replicate the instance of the file or portion thereof on the second storage tier and associate the replicated instance of the file or portion thereof on the second storage tier with the first user; and disassociate an instance of the file on a first storage tier from the first user.

Abstract: A storage system according to one embodiment includes a first storage tier; a second storage tier; logic for storing instances of a file in the first storage tier and the second storage tier; logic for determining an ownership status for each instance of the file in the storage system, wherein the ownership status includes owned and unowned; logic for determining a location of each instance of the file in the storage system; logic for determining whether each instance of the file in the first storage tier is being accessed or not being accessed; logic for assigning each instance of the file to one of a plurality of indices using the determined ownership status, location, and whether the instance is being accessed; logic for receiving a request to access the file or instance thereof from a user; logic for selecting an instance of the file based on an assignment of the instance of the file to one of the indices; and logic for providing the user with access to the selected instance of the file or copy thereof.

Abstract: A storage system according to one embodiment includes a first storage tier; a second storage tier; logic for storing instances of a file in the first storage tier and the second storage tier; logic for determining when to migrate an instance of the file associated with a first user and stored on the first storage tier to the second storage tier; logic for searching for an instance of the file or portion thereof on the second storage tier that is not associated with any user; logic for associating the instance of the file or portion thereof on the second storage tier with the first user; and logic for disassociating the instance of the file on the first storage tier from the first user. Additional systems, methods, and computer program products are also presented.

Abstract: A method, system and program are provided for enabling selective access to multiple users' encrypted data in a single storage cartridge. A unique, derived key is generated for each user's data by performing cryptographic operations on a combination of a common base key and metadata related to the data to be encrypted (e.g. its total block count). The base data key is wrapped with one or more encryption keys to form one or more encryption encapsulated data keys (EEDKs). The base key and the derived key are wrapped to create a session encrypted data key (SEDK), which along with the EEDKs, are conveyed to the tape drive, where the SEDK is decrypted. The EEDKs are then stored in one or more places on the storage cartridge. The base key and the derived key are used to encrypt a predetermined user's data, with the derived key stored on the cartridge with the encrypted data. The encrypted data may be subsequently decrypted by retrieving the EEDK and decrypting it with a decryption key to extract the base data key.

Abstract: Provided are a computer program product, system, and method for generating a code alphabet for use by a deployed program to determine codewords for words. A first code alphabet is generated having a first number of symbols that provide variable length codings of the words. The symbols in the first code alphabet are merged into a second number of groups of the symbols in the first code alphabet, where the second number is less than the first number. A second code alphabet is generated having the second number of symbols, wherein a second average codeword length of the codewords produced using the symbols in the second code alphabet is smaller than the codeword length (b) of the words, and wherein the second code alphabet comprises the code alphabet used by the deployed program.

Abstract: Provided are a computer program product, system, method, and data structure for using variable length code tables to compress an input data stream to a compressed output data stream. A determination is made as to whether a number of at least two consecutive data units in the input data stream match the number of consecutive data units in a history buffer of previously received data units in the input data stream. If so, a copy pointer symbol is generated including data indicating a copy pointer symbol referencing previously received data units in the history buffer and indicating the determined number of consecutive data units. A determination is made of a relative displacement count in the history buffer at which the number of matching consecutive data units start. A determination is made from a variable length code table an encoding of the relative displacement count in the history buffer.

Abstract: Provided are a computer program product, system, method, and data structure for using variable length code tables to compress an input data stream to a compressed output data stream. A determination is made as to whether a number of at least two consecutive data units in the input data stream match the number of consecutive data units in a history buffer of previously received data units in the input data stream. If so, a copy pointer symbol is generated including data indicating a copy pointer symbol referencing previously received data units in the history buffer and indicating the determined number of consecutive data units. A determination is made of a relative displacement count in the history buffer at which the number of matching consecutive data units start. A determination is made from a variable length code table an encoding of the relative displacement count in the history buffer.

Abstract: Provided are a computer program product, system, method, and data structure for using variable length code tables to compress an input data stream to a compressed output data stream. If a number of consecutive data units in the input data stream match the number of consecutive data units in a history buffer of previously received data units in the input data stream, a copy pointer symbol is generated indicating the copy pointer symbol referencing previously received data units in the history buffer and indicating a location of a start of the consecutive data units in the history buffer. A determination is made from a variable length code table of an encoding of the number. Indication is made in the generated copy pointer symbol the determined encoding of the number and the copy pointer symbol is outputted in the compressed output data stream.

Abstract: According to one embodiment, a method includes storing instances of a file in a first storage tier and a second storage tier of a storage system; associating each instance of the file on the first and second storage tier with a unique program identifier (UPI); receiving a request to access the file or instance thereof from a user in a group of users; searching for a UPI associated with an instance of the file that exists on the first storage tier; and providing the user requesting access to the file with remote access to the instance of the file on the first storage tier. Additional methods are also presented.

Abstract: Method, system, and computer program product embodiments for recording data on a contactless integrated circuit (IC) memory associated with a data storage cartridge are provided. In one exemplary embodiment, an index of a plurality of files to be recorded on a storage media of the data storage cartridge is parsed with a table of contents (TOC) profile file to build a table of contents (TOC) specific to an owning application of the plurality of files. The TOC is written to the contactless IC memory.

Abstract: Method, system, and computer program product embodiments for recording data on a contactless integrated circuit (IC) memory associated with a data storage cartridge are provided. In one exemplary embodiment, an index of a plurality of files to be recorded on a storage media of the data storage cartridge is parsed with a table of contents (TOC) profile file to build a table of contents (TOC) specific to an owning application of the plurality of files. The TOC is written to the contactless IC memory.

Abstract: A method and apparatus for providing error correction capability to longitudinal position data are disclosed. Initially, data are encoded via a set of even LPOS words and a set of odd LPOS words. The encoded data are then decoded by generating a set of syndrome bits for each of the LPOS words. A determination is then made as to whether or not there is an error within one of the LPOS words based on its corresponding syndrome bits.

Abstract: A storage system according to one embodiment includes a first storage tier; a second storage tier; logic for storing instances of a file in the first storage tier and the second storage tier; logic for determining an ownership status for each instance of the file in the storage system, wherein the ownership status includes owned and unowned; logic for determining a location of each instance of the file in the storage system; logic for determining whether each instance of the file in the first storage tier is being accessed or not being accessed; logic for assigning each instance of the file to one of a plurality of indices using the determined ownership status, location, and whether the instance is being accessed; logic for receiving a request to access the file or instance thereof from a user; logic for selecting an instance of the file based on an assignment of the instance of the file to one of the indices; and logic for providing the user with access to the selected instance of the file or copy thereof.

Abstract: A storage system according to one embodiment includes a first storage tier; a second storage tier; logic for storing instances of a file in the first storage tier and the second storage tier; logic for associating each instance of the file on the first and second storage tier with a unique program identifier (UPI); logic for receiving a request to access the file or instance thereof from a user in a group of users; logic for searching for a UPI associated with an instance of the file that exists on the first storage tier; and logic for providing the user requesting access to the file with remote access to the instance of the file on the first storage tier. Additional systems, methods, and computer program products are also presented.

Abstract: A storage system according to one embodiment includes a first storage tier; a second storage tier; logic for storing instances of a file in the first storage tier and the second storage tier; logic for receiving a request to access the file or instance thereof from a user in a group of users; logic for providing the user requesting access to the file with remote access to an instance of the file on the first storage tier that is not being used by any other user in the group of users; logic for setting an ownership status of the instance of the file on the first storage tier to owned by the user requesting access to the file; and logic for setting an ownership status of an unused instance of the file on the second storage tier from owned by the user requesting access to the file to unowned or owned by a second user which previously owned the instance of the file on the first storage tier. Additional systems, methods, and computer program products are also presented.

Abstract: A storage system according to one embodiment includes a first storage tier; an intermediate storage tier; a second storage tier; logic for storing instances of a file in the first storage tier, the intermediate storage tier, and the second storage tier; logic for determining which of a plurality of instances of the file in the first storage tier are to be migrated to the second storage tier; logic for copying one instance of the file from the first storage tier to the intermediate storage tier; and logic for copying the instance of the file from the intermediate storage tier to the second storage tier for creating an instance of the file on the second storage tier for each instance of the file on the first storage tier that is to be migrated to the second storage tier. Additional systems, methods, and computer program products are also presented.

Abstract: A storage system according to one embodiment includes a first storage tier; a second storage tier; logic for storing instances of a file in the first storage tier and the second storage tier; logic for determining when to migrate an instance of the file associated with a first user and stored on the first storage tier to the second storage tier; logic for searching for an instance of the file or portion thereof on the second storage tier that is not associated with any user; logic for associating the instance of the file or portion thereof on the second storage tier with the first user; and logic for disassociating the instance of the file on the first storage tier from the first user. Additional systems, methods, and computer program products are also presented.

Abstract: A method and apparatus for providing error correction capability to longitudinal position data are disclosed. Initially, data are encoded via a set of even LPOS words and a set of odd LPOS words. The encoded data are then decoded by generating a set of syndrome bits for each of the LPOS words. A determination is then made as to whether or not there is an error within one of the LPOS words based on its corresponding syndrome bits.

Abstract: Various embodiments for writing data in a tape medium having wraps by a tape drive are provided. The tape drive allocates the wraps in a shingled data band between two or more data partitions. A set of contiguous wraps is allocated to one data partition of the two or more data partitions. An additional set of contiguous wraps is allocated to an additional data partition of the two or more data partitions. A minimum buffer is retained between the set and the additional set of contiguous wraps of at least one wrap per direction written within at least one data band shared between the one and the additional data partitions such that the one and the additional data partitions may be written to by the tape drive independently of each other.