Abstract: Methods and apparatus associated with data cold storage are described. Example apparatus include an array of data storage devices arranged in rows and columns. Columns of the array are orthogonal to rows. A row has an associated row-centric power supply, and a column has an associated column-centric local electronics module (LEM) that controls a data storage device in the column independently of other data storage devices in the array. Example apparatus include logics that control a power mode of a data storage device independently of other data storage devices in the array, that control a power mode of an LEM, that adaptively regulate the level of data stored in a buffer, and that determine whether a data object will be stored in the buffer or stored on a data storage device in the array, based on the probability the data object will be accessed within a threshold period of time.

Abstract: A tape layout module for determining a tape layout allocation strategy for laying out data on tape, the data being organized into a plurality of fixed-size subdata sets with each of the plurality of subdata sets including a plurality of codeword interleaves, the tape including a plurality of media defect characteristics, includes a tape layout optimization system including a processor that receives information on the plurality of media defect characteristics. The tape layout optimization system determines the tape layout allocation strategy based at least in part on at least one of the plurality of media defect characteristics. Additionally, the tape layout optimization system can determine the tape layout allocation strategy further based on distance spectra between pairs of the plurality of codeword interleaves. Further, the tape layout optimization system can determine the tape layout allocation strategy by selectively utilizing at least one tape layout parameter.

Abstract: Embodiments disclosed herein provide systems, methods, and computer readable media for storing data to a plurality of physical storage volumes. In a particular embodiment, a method provides identifying first data for storage on the plurality of physical storage volumes. Each of the plurality of storage volumes corresponds to respective ones of a plurality of data channels. The method further provides segmenting the first data into a plurality of data segments corresponding to respective ones of the plurality of data channels and transferring the plurality of data segments as respective bit streams over the respective ones of the plurality of data channels to the respective ones of the plurality of physical storage volumes. The plurality of storage volumes stores the respective bit streams in the exact condition in which the bit streams are received.

Abstract: Methods and apparatus deduplicate and erasure code a message in a data storage system. One example apparatus includes a first chunking circuit that generates a set of data chunks from a message, an outer precoding circuit that generates a set of precoded data chunks and a set of parity symbols from the set of data chunks, a second chunking circuit that generates a set of chunked parity symbols from the set of parity symbols, a deduplication circuit that generates a set of deduplicated data chunks by deduplicating the set of precoded chunks or the set of chunked parity symbols, an unequal error protection (UEP) circuit that generates an encoded message from the set of deduplicated data chunks, and a storage circuit that controls the data storage system to store the set of deduplicated data chunks, the set of parity symbols, or the encoded message.

Abstract: Embodiments disclosed herein provide systems, methods, and computer-readable media to implement an object store with removable storage media. In a particular embodiment, a method provides identifying first data for storage on a first removable storage medium and designating at least a portion of the first data to a first data object. The method further provides determining a first location where to store the first data object in a first value store partition of the first removable storage medium and writing the first data object to the first location. Also, the method provides writing a first key that identifies the first data object and indicates the first location to a first key store partition of the first removable storage medium.

Abstract: Methods, apparatus, and other embodiments associated with doubly distributing erasure encoded data in a data storage system are described. One example apparatus includes a set of data storage devices and a set of logics that includes an encoding logic that generates an erasure encoded object that includes code-words, and chunks the code-words into code-word chunks, and a distribution logic that interleaves members of the set of code-word chunks into a plurality of records, and distributes the records across the data storage devices and within individual data storage devices. Example apparatus may include a read logic that reads the plurality of stored records from the data storage devices, and ignores read errors, and a repair logic that monitors the set of data storage devices, replaces or repairs failing data storage devices, generates replacement records, and stores the replacement records on a replacement data storage device.

Abstract: A method for reducing the number of error events in a transmitted data stream (34) comprises the steps of (i) generating at least a first most probable sequence (16(1)) and a second most probable sequence (16(2)) with a detection algorithm (12); (ii) determining if a first correctable error occurred in the first most probable sequence (16(1)) with an EDC decoder (14); and (iii) determining if a second correctable error occurred in the second most probable sequence (16(2)) with the EDC decoder (14). Additionally, the steps of determining if a first correctable error occurred and determining if a second correctable error occurred can be performed substantially simultaneously. The method can further comprise computing a plurality of path metrics (42) for the transmitted data stream (34); and selecting a first q smallest path metrics out of the first and second most probable sequences (16(1)), (16(2)) with a Q value selector (44).