38results about "Linear tape open format" patented technology

In one embodiment, a method includes loading a tape cartridge into at least one tape drive installed in an automated tape library, where a tape of the tape cartridge has at least two partitions; writing plurality of data blocks on a first of the partitions; and writing an index on a second of the partitions, wherein the index includes information about at least one of files and the blocks on the first partition.

An unencoded m-bit data input sequence is divided into a block of n bits and a block of m-n bits. The block of n bits is divided into a first set of n+1 encoded bits, wherein at least one of P1 subblocks of the first set satisfies a G, M and I constraints. The first set of n+1 encoded bits is mapped into a second set of n+1 encoded bits wherein at least one of P2 subblocks of the second set gives rise to at least Q1 transitions after 1 / (1+D2) precoding. A second set of n+1 encoded bits is divided into P3 encoded subblocks and the P3 encoded subblocks are interleaved among (m−n) / s unencoded symbols so as to form a (m+1)-bit output sequence codeword which is then stored on a data storage medium.

A method for physically laying out data on tape is disclosed herein. In one embodiment, such a method includes receiving a data set, wherein the data set includes S sub data sets (SDSs) of fixed size and each SDS includes N codeword interleaves (CWIs). The method further distributes the CWIs for the S SDSs across T tracks on a physical tape medium such that the distances between CWIs of the same SDS are substantially maximized on the physical tape medium. To maximize the distances, the method periodically rotates the tracks within the data set by a track rotation value R, wherein the number of tracks T is equal to 2k, and the track rotation value R is equal to 2k−1−1. A corresponding apparatus is also disclosed herein.

An object of the present invention is to embed information while making effective use of a recording area at the time of recording data. To this end, a controller in a tape drive includes: a storage unit which stores information desired to be embedded; an acquisition unit which acquires the information stored in the storage unit; a writing unit which repeatedly writes a CQ set determined on the basis of the acquired information the number of times determined on the basis of this information; a reading unit which reads data in which information is embedded; and an identification unit which identifies information embedded in the read data, and which determines whether or not the read data can be used and the like, in comparison with this information and the information stored in the storage unit.

In one embodiment, a data storage system includes a tape channel for reading data from a tape to produce a signal, an adaptive noise whitening filter adapted for receiving the signal, the noise whitening filter being adapted for minimizing variance of noise affecting the signal output from the noise whitening filter, a soft DMAX detector adapted for receiving the signal from the noise whitening filter, the soft detector adapted for calculating first soft information about each bit of the signal and sending the first soft information to a soft decoder, and the soft decoder positioned subsequent to the soft detector, the soft decoder being adapted for calculating second soft information about each bit of the signal and sending the second soft information to the soft DMAX detector, wherein one or more noise whitening coefficients used in the noise whitening filter are updated using a noise whitening filter coefficient updater.

In one embodiment, a method includes writing data to a storage medium of a data storage system using a partial reverse concatenated modulation code by encoding data sets using a C2 encoding scheme, adding a header to each subunit of the data sets, encoding the headers of the data sets with a first modulation encoding scheme, encoding data portions of the data sets with a second modulation encoding scheme, encoding portions of the one or more C2-encoded data sets using a C1 encoding scheme, combining the C1-encoded portions with the modulation-encoded headers of the C2-encoded data sets using a multiplexer, and writing the one or more combined C1- and C2-encoded data sets to data tracks of the storage medium. Other methods for writing data to a storage medium of a data storage system using a partial reverse concatenated modulation code are presented according to more embodiments.

In one embodiment, a data storage system includes a write channel for writing data to a storage medium, the write channel configured to utilize a partial reverse concatenated modulation code. The write channel includes logic adapted for encoding data sets using a C2 encoding scheme, logic adapted for adding a header to each subunit of the data sets, logic adapted for encoding the headers of the data sets with a first modulation encoding scheme, logic adapted for encoding data portions of the data sets with a second modulation encoding scheme, logic adapted for encoding portions of the one or more C2-encoded data sets using a C1 encoding scheme, logic adapted for combining the C1-encoded portions with the modulation-encoded headers of the C2-encoded data sets using a multiplexer, and logic adapted for writing the one or more combined C1 - and C2-encoded data sets to data tracks.

In one embodiment, a method includes determining a reading performance based on one or more metrics, adjusting a commanded lateral reading location of a head relative to a medium, determining the reading performance after the adjusting, comparing the reading performance after the adjusting relative to the reading performance before the adjusting for determining whether the reading performance has improved, and selecting a commanded lateral reading location based on the comparing. In another embodiment, a controller is configured to perform the foregoing method. In yet another embodiment, a computer program product includes a computer readable storage medium having program instructions embodied therewith, the program instructions readable and / or executable by a controller configured to perform the foregoing method.