Abstract: An apparatus includes a loop filter that receives a plurality of input signals. Each of the input signals is based on a different timing error detector output signal. The apparatus also includes a plurality of read channels, a plurality of interpolation filters, and an array of transducers. Each of the interpolation filters is in communication with a corresponding one of the read channels. Each of the transducers is in communication with a corresponding one of the read channels. The loop filter processes the plurality of input signals, and outputs a different total phase signal for each received input signal. Each of the interpolation filters samples the corresponding read channel based on one of the total phase signals output by the loop filter. The loop filter processes the plurality of input signals by calculating a phase estimate of the samples, and a skew estimate of the samples, relative to written data.

Abstract: A storage system is proposed which comprises a data storage device including a number N of removable storage media for storing data, with N?2, and a number m of drives, with m?1, wherein each of the m drives is configured to drive one of the removable storage media mounted to the drive. The storage system includes a server being coupled to the data storage device and configured to serve requests from clients, and a controller which is configured to control the data storage device to adaptively unmount the removable storage media based on a monitoring information of the requests at the data storage device, states of the drives, and states of the removable storage media.

Abstract: In one general embodiment, a method includes determining a sampling interval for an interpolator using at least one of: predefined data stored in memory, and a standard deviation of a position error signal. The method further includes applying the sampling interval to the interpolator in response to determining the sampling interval. In another general embodiment, an apparatus includes an interpolator and a controller. The controller is configured to determine a sampling interval for the interpolator using at least one of: predefined data stored in memory, and a standard deviation of a position error signal. The controller is also configured to apply the sampling interval to the interpolator in response to determining the sampling interval.

Abstract: A computer program product is provided for performing symbol timing recovery in a parallel recording channel system. The computer program product comprises a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processor to cause the processor to receive a plurality of timing-error estimates for a plurality of read channels. Each of the timing-error estimates corresponds to one of the read channels. Also, the program instructions are executable by the processor to cause the processor to calculate a common phase based on the plurality of timing-error estimates. Moreover, the program instructions are executable by the processor to cause the processor to calculate a skew of a transducer array based on the plurality of timing-error estimates, and to calculate a different total phase estimate for each read channel based on the calculated common phase and the calculated skew of the transducer array.

Abstract: The present invention is notably directed to a computer-implemented method of accessing data by an application. The method comprises detecting an application that is accessing an initial file stored in a storage system; fetching an application model of the detected application, the application model comprising an association between access patterns of the detected application when accessing first files with first metadata information of the said first files; identifying one or more second files stored in the storage system, the identified one or more second files having second metadata information that are similar to the first metadata information; and prefetching the identified one or more second files.

Abstract: In one embodiment, a tape drive includes a controller including a processor and logic integrated with and/or executable by the processor. The logic is configured to obtain at least two periodic waveform components of a high density (HD) servo signal read by a servo reader from a HD pattern written on a servo band of a magnetic tape medium. The logic is also configured to filter the HD servo signal using a number of digital filters that are configurable to detect waveform components simultaneously read from the magnetic tape medium, each digital filter being configured to match waveform component parameters and tape velocity. Moreover, the logic is configured to compute a position error signal (PES) based on the filtering of the HD servo signal comprising the waveform components.

Abstract: An apparatus includes a loop filter that receives a plurality of input signals. Each of the input signals is based on a different timing error detector output signal. The apparatus also includes a plurality of read channels, a plurality of interpolation filters, and an array of transducers. Each of the interpolation filters is in communication with a corresponding one of the read channels. Each of the transducers is in communication with a corresponding one of the read channels. The loop filter processes the plurality of input signals, and outputs a different total phase signal for each received input signal. Each of the interpolation filters samples the corresponding read channel based on one of the total phase signals output by the loop filter. The loop filter processes the plurality of input signals by calculating a phase estimate of the samples, and a skew estimate of the samples, relative to written data.

Abstract: A computer program product is provided for performing symbol timing recovery in a parallel recording channel system. The computer program product comprises a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processor to cause the processor to receive a plurality of timing-error estimates for a plurality of read channels. Each of the timing-error estimates corresponds to one of the read channels. Also, the program instructions are executable by the processor to cause the processor to calculate a common phase based on the plurality of timing-error estimates. Moreover, the program instructions are executable by the processor to cause the processor to calculate a skew of a transducer array based on the plurality of timing-error estimates, and to calculate a different total phase estimate for each read channel based on the calculated common phase and the calculated skew of the transducer array.

Abstract: A tape head assembly includes a set of data readers configured to simultaneously read data from a set of adjacent data tracks of a tape storage medium, each data track having a width; wherein the width of each data reader of the set along a lateral extension of the tape head assembly is equal to or less than the width of a data track wherein the lateral extension of the tape head assembly is orthogonal to a longitudinal extension of the tape storage medium when arranged in a tape drive containing the tape head assembly spanning at least the set of data tracks during reading; and a servo reader arrangement containing at least one servo reader arranged laterally offset from one of the data readers by less than the width of a data track.

Abstract: A tape head assembly includes a set of data readers configured to simultaneously read data from a set of adjacent data tracks of a tape storage medium, each data track having a width; wherein the width of each data reader of the set along a lateral extension of the tape head assembly is equal to or less than the width of a data track wherein the lateral extension of the tape head assembly is orthogonal to a longitudinal extension of the tape storage medium when arranged in a tape drive containing the tape head assembly spanning at least the set of data tracks during reading; and a servo reader arrangement containing at least one servo reader arranged laterally offset from one of the data readers by less than the width of a data track.

Abstract: In one general embodiment, a method includes determining a sampling interval for an interpolator using at least one of: predefined data stored in memory, and a standard deviation of a position error signal. The method further includes applying the sampling interval to the interpolator in response to determining the sampling interval. In another general embodiment, an apparatus includes an interpolator and a controller. The controller is configured to determine a sampling interval for the interpolator using at least one of: predefined data stored in memory, and a standard deviation of a position error signal. The controller is also configured to apply the sampling interval to the interpolator in response to determining the sampling interval.

Abstract: A control device for controlling the transport of a tape within a tape transport system, the tape transport system having a head being operable to read data from and/or write data to the tape, an outboard reel and an inboard reel, wherein the tape is moveable from the outboard reel to the inboard reel in forward direction or from the inboard reel to the outboard reel in reverse direction, wherein the control device is adapted to generate control signals to control the velocity of the outboard reel and the velocity of the inboard reel as a function of a primary velocity of the tape at the head and a secondary velocity of the tape at the inboard reel and/or a secondary velocity of the tape at the outboard reel.

Abstract: An apparatus for operating a tape storage device comprises a tape skew estimation unit for estimating a value related to a skew of a tape storage medium arranged in the tape storage device relative to a head module of the tape storage device. A servo pattern decoder is configured to decode information encoded in a servo pattern written to one or more servo bands of the tape storage medium based on read-back signals of at least two servo readers of the tape storage device arranged for reading the servo pattern from the one or more servo bands and based on the estimated skew related value.

Abstract: A tape head assembly includes a set of data readers configured to simultaneously read data from a set of adjacent data tracks of a tape storage medium, each data track having a width; wherein the width of each data reader of the set along a lateral extension of the tape head assembly is equal to or less than the width of a data track wherein the lateral extension of the tape head assembly is orthogonal to a longitudinal extension of the tape storage medium when arranged in a tape drive containing the tape head assembly spanning at least the set of data tracks during reading; and a servo reader arrangement containing at least one servo reader arranged laterally offset from one of the data readers by less than the width of a data track.

Abstract: A tape head includes a set of one or more segments, wherein each segment of the set is individually movable with respect to a frame; each segment of the set comprising at least one of a write element configured to write data to a tape and a read element configured to read data from the tape; and each segment of the set comprising a further read element having a width transverse to a motion direction of the tape being at least a width of the write element of the segment or, in the event that no write element is comprised in the segment, of a write element of a different segment.

Abstract: A magnetic tape storage medium includes at least one servo band with at least two sub-bands along a longitudinal extension of the medium. Servo bursts are written to the sub-bands to determine positional information of the medium. A first of the sub-bands includes a first burst with at least one servo stripe inclined at a first non-zero angle with respect to a direction orthogonal to the longitudinal extension of the medium followed by a second burst comprising at least one servo stripe inclined at a second non-zero angle with respect to the direction orthogonal to the longitudinal extension of the medium, which second angle is different from the first angle. A second of the sub-bands includes a first burst having at least one servo stripe followed by a second burst having at least one servo stripe, the first and the second bursts parallel to each other.

Abstract: In one embodiment, a magnetic data storage apparatus includes a magnetic head having at least one group of N servo readers, a drive mechanism for passing a linear magnetic recording medium over the head, and a controller electrically coupled to the head. The controller is configured to position a first servo reader of the at least one group of N servo readers in a first lateral medium region of the recording medium with a servo band having a width b that is less than or equal to about 1.2 B/N, where N is an integer greater than or equal to 2, and B corresponds to a distance between data read/write transducers of the magnetic head, and position the magnetic head in a second lateral region of width b with a second servo reader of the at least one group of N servo readers for reading the servo band.

Abstract: In one embodiment, a system for processing data includes an equalizer having a finite impulse response (FIR) filter configured to process data read with a channel using servo coefficients to generate equalized data, and one or more low-pass filters configured to filter the equalized data to output filtered data. The one or more low-pass filters is configured to remove high frequency noise from the equalized data. A method for processing data in a read channel, in one embodiment, includes receiving data read from a magnetic tape using the read channel of a magnetic tape drive. A finite impulse response (FIR) filter is applied to the data by an equalizer using servo coefficients to output equalized data. One or more low-pass filters is applied to the equalized data to obtain filtered data, the one or more low-pass filters being configured to remove high frequency noise from the equalized data.

Abstract: A storage system is proposed which comprises a data storage device including a number N of removable storage media for storing data, with N?2, and a number m of drives, with m?1, wherein each of the m drives is configured to drive one of the removable storage media mounted to the drive. The storage system includes a server being coupled to the data storage device and configured to serve requests from clients, and a controller which is configured to control the data storage device to adaptively unmount the removable storage media based on a monitoring information of the requests at the data storage device, states of the drives, and states of the removable storage media.

Abstract: A tape head assembly includes a set of data readers configured to simultaneously read data from a set of adjacent data tracks of a tape storage medium, each data track having a width; wherein the width of each data reader of the set along a lateral extension of the tape head assembly is equal to or less than the width of a data track wherein the lateral extension of the tape head assembly is orthogonal to a longitudinal extension of the tape storage medium when arranged in a tape drive containing the tape head assembly spanning at least the set of data tracks during reading; and a servo reader arrangement containing at least one servo reader arranged laterally offset from one of the data readers by less than the width of a data track.