International Business Machines Corporation

Lenovo (singapore) Pte. Ltd.

Tsuyoshi Miyamura

Noriko Yamamoto

Tohru Hasegawa

Hiroshi Itagaki

Shinsuke Mitsuma

Sosuke Matsui

Atsushi Abe

Setsuko Masuda

Terue Watanabe

Norie Iwasaki

Eiji Ogura

Tomoko Taketomi

Kazuhiro Tsuruta

Tatsuki Sawada

Takashi Ashida

Ernest Stewart Gale

Mitsuhiro Nishida

Keisuke Tanaka

Tomoaki Kimura

Kevin Bruce Judd

Randy Clark Inch

Pamela Ruth Nylander-Hill

Tatsushi Hakuchoh

Nhan Xuan Bui

Yutaka Oishi

Lucas Correia Villa Real

Takashi Sugawara

Takuya Ishikawa

Takahiro Tsuda

Kohei Taguchi

Hironobu Nagura

Tomoki Maruichi

Yuka Sasaki

Hiroki Nishiyama

Tsuyoshi Kamenoue

Kohji Kawahara

Kenji Mikuni

Hiroshi Itakagi

Aspects of the present disclosure relate to improved tape repositioning. Information associated with at least one preceding dataset on a tape medium is stored within a dataset information table (DSIT) of a dataset on the tape medium. A repositioning request specifying a target data position is received. The information associated with the at least one preceding dataset within the DSIT of the dataset is referenced while attempting to complete the repositioning request.

Tape drive repositioning

A computer implemented method includes identifying a set of target files to be migrated from a primary storage to a secondary storage, extracting text data from the set of target files, identifying a set of keywords corresponding to the extracted text data from the set of target files, determining a number of keyword appearances in each file of the set of target files, assigning an order of migration corresponding to the set of target files such that the target files are written to the secondary storage in order of decreasing number of keywords, and migrating the files to the secondary storage according to the assigned order of migration. The method may additionally include writing the files with the greatest number of keywords closest to the default position of the tape reader. A computer program product and computer system corresponding to the method are also disclosed herein.

Re-ordering files by keyword for migration

A computer-implemented method, a computer program product, and a computer system for repositioning operation on a tape medium based on dataset information. A computer system obtains dataset information of a dataset on a tape medium in a sync operation, where the dataset information includes positions of data in the dataset. A computer system sends the dataset information of the dataset to a host. In response to starting a repositioning operation, a computer system receives from the host the dataset information of the dataset. A computer system reads the dataset information of the dataset. A computer system repositions to a target on the tape medium, based on the dataset information of the dataset, where a tape drive refers to the dataset information and moves to a position immediately before the target.

Repositioning operation on a tape medium based on dataset information

A computer implemented method includes receiving a list of areas on a subject tape to be read, wherein each area of the list of areas is indicated by a first record number and a last record number corresponding to the area, identifying parameters of a tape drive configured to read the subject tape, wherein the identified parameters of the tape drive contribute to a speed with which the tape drive can read the list of areas, creating a directed graph of the areas on the subject tape based on the identified parameters, wherein the directed graph indicates how long the tape drive will take to read the areas on the subject tape, and determining a fastest reading order of the areas on the subject tape, based, at least in part, on the directed graph and the identified parameters. A computer program product and computer system are also disclosed.

Read order determination on a tape

Provided are a computer program product, system, and method for managing access to tape cartridges at a tape archival service provider. A determination is made as to whether a non-volatile memory of the tape cartridge stores a key encryption key comprising an encrypted user encryption key associated with a user. In response to determining that the non-volatile memory of the tape cartridge stores the key encryption key, the key encryption key is decrypted to produce the user encryption key. The user encryption key, resulting from the decrypting, is provided to an encryption engine of the tape drive to encrypt plain-text data read from the tape medium in the tape cartridge with the user encryption key to return to a read request.

Managing access to tape cartridges at a tape archival service provider

A method for writing to tape by a tape drive is provided. The method includes, in response to identifying a write error during a write to a tape in a certain HRTD region, repositioning the tape to a next HRTD region. The method further includes continuing the write at the next HRTD region.

Tape drive write across write error

A system for recalling data from tape is disclosed. The system includes computer processing circuits and computer readable storage media having computer executable instructions. When executed, the instructions cause the computer-processing circuits to start, in response to a request to recall data from a tape, to read the tape at a read position. Additionally, the instructions cause the circuits to determine that the tape comprises a damaged region. Further, the instructions cause the circuits to determine a start position of the damaged region by skimming the tape. Additionally, the instructions cause the circuits to determine an end position of the damaged region by skimming the tape. Further, the instructions cause the circuits to read between the read position and the start position of the damaged region. Additionally, the instructions cause the circuits to read between the end position of the damaged region and an end of data indicator.

Recalling data from tape

A method for creating a Full Data Set Directory (FDSD) entry, in accordance with one embodiment, includes acquiring a record count and file mark count of a data set written to and/or to be written to a magnetic recording tape. A writing position on the tape where the data set will be written is determined. The data set is written on the tape. An FDSD entry is generated for the data set. The FDSD entry includes information about each of the following: a tape write pass in which the data set is written, a position of the data set on the tape, the record count, and the file mark count.

Full data set directory for magnetic tape recording media

A tool for tape library hierarchical storage management. The tool determines there is available tape capacity on a tape cartridge mounted to a tape drive to migrate data from a migration queue during recall operations. The tool sends a locate end of data (EOD) command to the tape drive. The tool determines the migration queue is within a longitudinal position (LPOS) range. The tool writes data from the migration queue to the tape cartridge within the LPOS range.

Appending data to a tape cartridge during recall operations

An End of Data Set (EOD) including a High Resolution Tape Directory (HRTD) is written at a position next to a last written user data set on a tape. When appending a new user data set, the new user data set is written starting from a position next to an end longitudinal position (LPOS) of the EOD to generate an overwritten EOD.

Retaining high resolution tape directory in overwritten end of data set

A computer-implemented method for altering a current position in a Data Partition of a tape at which the tape transitions to a DATA_FULL state is disclosed. The computer-implemented method includes determining a size of a last Index appended to the Data Partition of the tape. The computer-implemented method further includes altering, based on the size of the last Index appended to the Data Partition of the tape, the current position in the Data Partition of the tape at which the tape transitions to DATA_FULL state to a new position in the DATA Partition of the tape at which the tape transitions to the DATA_FULL state, wherein the DATA_FULL state is a state on the tape in which only metadata write operations are permitted in the Data Partition.

Dynamic tape storage device data buffer

Provided is a system, method, and computer program product for minimizing high resolution tape directory (HRTD) recovery time when a HRTD is invalid. A tape drive may load a tape in the tape drive. In response to receiving a write command or a read command at a beginning of tape (BOT) position, the tape drive may execute the write command or the read command without performing HRTD recovery. In response to receiving the write command or the read command at a position other than the BOT position, the tape drive may determine if the HRTD is valid. In response to determining the HRTD is not valid, the tape drive may clear a timer.

Minimizing high resolution tape directory recovery time

Described are techniques for a tape unmounting protocol. The techniques include selecting a tape for unmounting from a plurality of tape drives, where the tape for unmounting includes a remaining capacity below a first threshold and a number of migrated files below a second threshold. The techniques further include unmounting the tape for unmounting from a tape drive.

Tape unmounting protocol

An approach for deleting a file from a primary file system. The approach deletes a directory entry, associated with a file, from an in-memory index associated with a secondary file system. The approach updates an index cache associated with a secondary file system, based on the in-memory index. The approach updates a dirty flag, associated with the secondary file system, to a value of TRUE.

Optimizing removable media library file removal

Embodiments of the present invention provide a system, method, and computer program product for offsetting a reading head on a magnetic tape to improve verification. A processor determines a write head width, a read head width, and a track pitch based on determining an LTO standard of the magnetic tape. The processor determines a distance of the reading head from a writing head using the write head width, the read head width, and the track pitch, and causes a tape appliance to relocate the read head on the magnetic tape to the determined distance.

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Yokohama, Japan

Tsuyoshi Miyamura