International Business Machines Corporation

Kazuhiro Tsuruta

Nhan Xuan Bui

Eiji Ogura

Giovanni Cherubini

Reed Alan Hancock

Jens Jelitto

Tomoko Taketomi

Randy Clark Inch

Glen Alan Jaquette

John Alexander Koski

Junichi Fukuda

Robert Allen Hutchins

Keisuke Tanaka

Tsuyoshi Miyamura

Roy Daron Cideciyan

Robert Allan Hutchins

Ernest Stewart Gale

Akimitsu Sasaki

Yutaka Oishi

Kevin Bruce Judd

Mark Allan Taylor

Simeon Furrer

James Howard Eaton

Mark Alfred Lantz

Angeliki Pantazi

Norie Iwasaki

Setsuko Masuda

Hiroshi Itagaki

Thomas Mittelholzer

Takashi Katagiri

Pamela Ruth Nylander-Hill

Yohichi Miwa

Izuru Narita

Yumi Mori

Shuhei Nadehara

Yoshikuni Murakami

Shinsuke Mitsuma

Atsushi Abe

Kenji Nakamura

Terue Watanabe

Edwin Ralph Childers

Larry LeeRoy Tretter

Takeo Yasuda

Steven Ross Bentley

Takeshi Inagaki

Shinobu Fujihara

Tomoaki Kimura

Josephine F Bayang

Melanie Jean Sandberg

Toshio Kanai

Satoshi Tohji

Malanie Jean Sandberg

David H Flores Harper

Wataru Ichihara

Robert Allen Hutchins, Iii

An apparatus for tape library management. The apparatus includes a storage slot that includes a plurality of mirrors integrated into the storage slot for reading a barcode affixed to each of a plurality of tape cartridges stored in a tiered orientation within the storage slot. The apparatus further includes wherein each of the plurality of mirrors are located directly below the barcode affixed to each of the plurality of tape cartridges stored in the storage slot. The apparatus further includes wherein each of the plurality of mirrors projects a reflection of the barcode affixed to each of the plurality of tape cartridges outward towards a front side of the storage slot.

Optimized re-inventory for a tape library

A tape drive-implemented method, according to one embodiment, includes: using information read from one or more servo bands on a magnetic tape to position a magnetic tape head relative to the magnetic tape. An array of data transducers is positioned along the magnetic tape head, the array extending perpendicular to a direction of travel of the magnetic tape. Moreover, a group of servo readers is positioned at each end of the array of data transducers. A distance between each of the immediately adjacent servo readers in each of the groups of servo readers is less than or equal to one third of a prespecified width of each of the servo bands. Furthermore, the distance between each of the servo readers in each of the groups and the prespecified width are both measured in a direction perpendicular to the direction of travel of the magnetic tape.

Hybrid servo pattern configurations for magnetic tape

A tape drive-implemented method, according to one embodiment, includes: detecting a read error, and sending one or more instructions to perform a first re-read attempt on a portion of a magnetic tape corresponding to the read error. In response to determining that the first re-read attempt was unsuccessful, a range of tension settings is selected. A range of lateral offsets is also selected. Moreover, one or more instructions are sent to apply each unique combination of a tension setting from the range of tension settings and a lateral offset from the range of lateral offsets. For each of the unique combinations applied, one or more instructions are sent to perform a second phase re-read attempt on the portion of the magnetic tape corresponding to the read error. Furthermore, a determination is made as to whether the second phase re-read attempt was performed successfully for any of the unique combinations.

Behavioral model for dynamic tension compensation

A method and system for a controlling a head element of a tape drive is disclosed. Y-position values based on servo bands are identified. Control adjustments for the head element are determined based on the Y-position values and the direction of the current wrap.

Safe head positioning based on y-position values in tape drive

A tape drive-implemented method, according to one embodiment, includes: detecting a read error, determining whether a current tension setting of the magnetic tape is accurate, determining whether the read error is part of an error burst in response to determining that the current tension setting of the magnetic tape is accurate, sending instructions to perform a first re-read attempt in response to determining that the read error is not part of an error burst, determining whether the first re-read attempt was performed successfully, selecting a range of tension settings in response to determining that the first re-read attempt was not performed successfully, selecting a range of lateral offsets, sending instructions to apply each unique combination of tension settings and lateral offsets, for each of the unique combinations applied, sending instructions to perform a second phase re-read attempt, and determining whether the second phase re-read attempt was performed successfully.

According to one embodiment, a system includes a controller configured to determine whether a position error signal (PES) is invalid while reading data from a magnetic medium using at least one data channel. An invalid PES indicates off-track reading or a defect in the magnetic medium. The controller is also configured to determine whether a PES value is above a first predetermined threshold in response to a determination that the PES is valid. Moreover, the controller is configured to inject error bits into a data stream in place of corresponding bits of decoded data in response to a determination that the PES is invalid, a determination that the PES value is above the first predetermined threshold, or a determination that the PES is invalid and the PES value is above the first predetermined threshold. Other systems and methods are described in accordance with more embodiments.

Reliable data reading with data set screening by error injection

A method and system for adjusting a servo head in a tape drive is disclosed. Position information for the servo head can be obtained and used to determine if an adjustment of one of the servo heads is necessary. By comparing the position of the tape against two servo heads, erroneous adjustments to the servo head can be obviated.

Dynamic head offset selection for tape drive

A tape drive-implemented method, according to one embodiment, includes: determining a servo band configuration of servo bands on a magnetic tape, using servo readers on a magnetic tape head to read one or more of the servo bands based on the determined servo band configuration, and using information read from the one or more of the servo bands to position the magnetic tape head relative to the magnetic tape. An array of data transducers is positioned along the magnetic tape head, the array extending perpendicular to a direction of travel of the magnetic tape. Moreover, a group of the servo readers is positioned at each end of the array of data transducers, and a distance between each of the immediately adjacent servo readers in each of the groups of servo readers is less than or equal to one third of a prespecified width of each of the servo bands.

Some embodiments of the present invention logically eliminate an end region of a user-data area of a magnetic storage tape during formatting (or re-formatting) of the tape, if the position error signal (PES) variance corresponding to the end region exceeds a threshold. An adjacent region, having a PES variance less than the threshold is designated as a new end region, thereby shortening the user-data area of the tape and extending its usable life.

Extending usable life of magnetic storage media

For avoiding debris accumulation on a tape drive, a processor records a position error signal (PES) value and cumulative head turnaround count for each region of a plurality of regions of a magnetic tape. The processor further selects a first region in which to reverse travel of the magnetic tape relative to a tape head. In response to determining one of the PES value for the first region does not exceed a PES threshold and the cumulative head turnaround count for the first region does not exceed a count threshold, the processor reverses travel of the magnetic tape at the first region. In response to determining the PES value for the first region exceeds the PES threshold and the cumulative head turnaround count for the first region exceeds the count threshold, the processor selects a second region at which to reverse travel of the magnetic tape.

Avoiding debris accumulation on tape drive

According to one embodiment, a system for processing data includes a controller configured to determine whether a position error signal (PES) is invalid while reading data from a magnetic medium using at least one data channel. The controller is also configured to determine whether a PES value is above a first predetermined threshold in response to a determination that the PES is valid. Moreover, the controller is configured to inject error bits into a data stream in place of corresponding bits of decoded data in response to a determination that the PES is invalid and in response to a determination that the PES value is above the first predetermined threshold. Other systems and methods for processing data are described in accordance with more embodiments.

In one embodiment, a computer-implemented method includes creating a spike in a servo channel from a predetermined start position to an end position, and storing servo data including at least a portion thereof generated during the spike. The spike has a predetermined amplitude. In another embodiment, a computer program product includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a controller to perform the foregoing method.

Generating defect signals in time based servo tape storage systems

In one embodiment, a computer-implemented method for simulating a defect signal in a time based servo system includes determining a start position for a spike, determining an end position for the spike, determining a servo channel, determining an amplitude of the spike, initiating an acquire lock process, creating the spike in the determined servo channel from the determined start position to the determined end position, and storing servo data including at least a portion thereof generated during the spike. The spike has the determined amplitude. In another embodiment, a computer program product for generating defect signals in a storage system includes a computer readable storage medium having program instructions embodied therewith, wherein the computer readable storage medium is not a transitory signal per se. The program instructions are executable by a controller to perform the foregoing method.

According to one embodiment, a method for processing data includes determining whether a PES is invalid while reading data from a magnetic medium using at least one data channel, determining whether a PES value is above a first predetermined threshold when the PES is valid, injecting error bits into a data stream in place of corresponding bits of decoded data when the PES is invalid and/or the PES value is above the first predetermined threshold, decoding the data using a run-length limited (RLL) decoder to produce the decoded data based on the data from the magnetic medium, and outputting the data stream. Other methods, systems, and tape drives for processing data using error injection are described in more embodiments.

Growing community of inventors

Sagamihara, Japan

Kazuhiro Tsuruta