38results about "Linear tape open format" patented technology

In one embodiment, a tape drive system includes a magnetic head having a servo sensor for sensing a defined servo track of a magnetic tape and configured to read servo pulses from servo bursts of the servo track while the magnetic tape is moving past the magnetic head with the servo bursts representing an encoded data symbol, an analog-to-digital converter configured to provide a sequence of samples of the readback servo signal, a digital correlator configured to compute a correlation signal between the sequence and a reference waveform, a timing reference module configured to provide a reference timing model having interpolation instants to the digital correlator, a correlation interpolator configured to interpolate the correlation signal at the interpolation instants and compute a longitudinal position (LPOS) detection metric, and an LPOS detector configured to decode the encoded data symbol of the servo bursts using the computed LPOS detection metric.

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

Described are embodiments of an invention for storing write environment conditions of a tape cartridge. A tape drive measures and stores the write environment conditions for a portion of tape as a result of receiving a write command to write data to the same portion of tape. In one embodiment, the write environment conditions are measured and stored to the tape cartridge each time a write command is received such that each portion of tape written has corresponding stored write environment conditions. The write environment conditions include temperature and relative humidity in one embodiment. The stored write environment conditions for each portion of tape written creates a historical log of the environment conditions that the tape was written within. The historical log can provide information to a manufacturer or user regarding the environmental conditions the user operates their tape drive within and provides information to assist with failure analysis.

The magnetic tape includes a non-magnetic support; a non-magnetic layer including a non-magnetic powder and a binding agent on the non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic layer, in which a total thickness of the non-magnetic layer and the magnetic layer is equal to or smaller than 0.60 μm, the magnetic layer has a servo pattern, and an isoelectric point of a surface zeta potential of the magnetic layer is equal to or greater than 5.5.

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 2^k, and the track rotation value R is equal to 2^k−1−1. A corresponding apparatus is also disclosed herein.

Methods, computer systems, and computer program products are provided for operating a tape drive comprising a tape medium with a plurality of record groups stored thereon. Access sequence for the plurality of record groups is provided. The tape medium is positioned for reading a record group in the access sequence before a seek command for the record group in the access sequence is received.

Provided are a method, servo channel, and tape drive for recovering servo information from a synchronous servo channel. An interpolator reads samples of a servo signal obtained from a servo reader at a rate of one servo sample per clock interval, to produce up to M interpolated servo samples per clock interval. A first buffer buffers interpolation time instants at which the interpolator generates interpolated servo samples. The interpolated servo samples are buffered in a second buffer and the interpolated servo samples are outputted from the second buffer to a correlator to produce correlation signal samples.

A method for randomizing data to mitigate false VFO detection is described. In one embodiment, such a method includes simultaneously receiving multiple input data streams. Each input data stream is associated with a different track on a magnetic tape medium. The input data streams are simultaneously scrambled to produce multiple randomized data streams. The input data streams are scrambled such that different bit patterns are produced in the randomized data streams even where corresponding bit patterns in the input data streams are identical. The randomized data streams are simultaneously written to their associated data tracks on the magnetic tape medium.

According to one aspect, a computer-implemented method includes receiving a request to read a plurality of files from a tape, and obtaining a tape directory identifying an area on the tape that stores the files. The tape directory is used to map each file to one of the regions on the tape where the respective file is stored. A first subset of files stored in the same first region on the tape is also ordered in a first order. The computer-implemented method also includes concurrently ordering a second subset of files stored in the same second region on the tape in a second order, and instructing the tape drive to read each file in the first subset according to the first order.