An apparatus according to an embodiment includes an array of transducers including an inner transducer and subarrays of the transducers positioned on opposite sides of the inner transducer, and a controller coupled to the transducers. The controller is configured to process data using only the transducers in the subarrays in a first mode of operation. Moreover, the controller is configured to process data using only a portion of the transducers in each of the subarrays in a second mode of operation, where the inner transducer is inactive in the second mode of operation.

In one embodiment, a drive-implemented method includes determining, by a tape drive, that a magnetic recording tape is compatible with a first format, the tape drive having an array of transducers including subarrays of the transducers positioned on opposite sides of an inner transducer, reading from or writing to the magnetic recording tape using the array in a first mode of operation corresponding to the first format, processing data using only transducers in the subarrays in the first mode of operation, and processing data using only a portion of transducers in each subarray in a second mode of operation corresponding to the second format. The first format specifies locations of data and a contiguous spare area on the tape and compatibility with a second format. The second format specifies a set of second active channels different than a set of first active channels specified by the first format.

Method, computer program product, and system embodiments of the present disclosure may include a computing device which may set a predetermined flag on data to be copied from a primary storage tier and a secondary storage tier. The computing device may identify a first portion of the flagged data as being in a pre-migrated state stored on the primary storage tier and migrate the flagged pre-migrated data from the primary storage tier to a target medium. The computing device may identify a second portion of the flagged data as being in a migrated state stored on the secondary storage tier. The computing device may recall the flagged migrated data from the secondary storage tier to the primary storage tier, and migrate the recalled migrated data from the primary storage tier to the target medium.

A tape method, according to one embodiment, includes: adjusting a position of a tape head in the tape drive relative to a magnetic tape such that the tape head is positioned at an accumulating backhitchless flush (ABF) wrap on the magnetic tape. A first index is also written in the ABF wrap. The first index corresponds to data written in a data partition on the magnetic tape, and the ABF wrap and the data partition are different partitions. Furthermore, in response to writing the first index in the ABF wrap, the position of the tape head is adjusted relative to the magnetic tape such that the tape head is positioned at the data partition. A first empty index is also appended to an end of the data written in the data partition, where a size of the first empty index is less than a size of the first index.

An apparatus according to one embodiment includes an array of 2N+1 transducers and a controller directly electrically coupled to each of the transducers, where the controller is configured to use transducers on only one side of a centerline of the array in a first mode of operation.

In one embodiment, a method includes writing a data set to a sequential access medium. The method also includes reading the data set after being written in a read-while-write process to identify faulty encoded data blocks, each of the faulty encoded data blocks including at least one faulty codeword. Moreover, the method includes rewriting a correct version of a first of the encoded data blocks in a first encoded data block set to the rewrite area of the sequential access medium selected from a predetermined subset of logical tracks. The predetermined subset of logical tracks includes D1+D2+1 logical tracks. Only one encoded data block from a particular sub data set is rewritten in a single encoded data block set in the rewrite area.

In one embodiment, a method includes writing a data set to a sequential access medium. The method also includes reading the data set immediately after being written to the sequential access medium in a read-while-write process to identify one or more faulty encoded data blocks, each of the one or more faulty encoded data blocks including at least one faulty codeword having symbols at least 10 bits in size. Moreover, the method includes rewriting a first of the one or more faulty encoded data blocks within a first encoded data block set to a particular logical track in the rewrite area of the sequential access medium selected from a predetermined subset of logical tracks. The predetermined subset of logical tracks includes D1+D2+1 logical tracks. Only one faulty encoded data block from a particular sub data set is rewritten in a single encoded data block set in the rewrite area.

A tape drive, according to one embodiment, includes: a processor, and logic which is integrated with the processor, executable by the processor, or integrated with and executable by the processor. The logic is configured to: determine whether a difference between information and corresponding design values is in a range. The information corresponds to how an array of writers write and/or are expected to write to a magnetic medium during shingled recording. Moreover, the logic is configured to: compute, using the information, data describing a lateral writing position to use during writing such that shingled track edges are aligned according to a format in response to determining that the difference between the information and corresponding design values is not in the range.

Mounting a data storage medium having information recorded thereon, where: the information is formatted according to a data storage format standard that includes first write and read functions, the information includes first and second datasets, the first dataset includes a first file mark, an index, and an empty space between the second dataset and a combination of the first file mark and the index; receiving, from a first application, a data block and a write command for writing the data block onto the data storage medium; and in response to receiving the write command: determining that the empty space is present in the first dataset, writing, by a second write function, the data block into the empty space, and writing a second file mark in the second dataset; wherein the empty space of the data storage medium is inaccessible to the first write function of the data storage format standard.

A computer-implemented method, according to one embodiment, includes: determining, by the computer, whether a difference between information and corresponding design values is in a range. The information corresponds to how an array of writers write and/or are expected to write to a magnetic medium during shingled recording. Moreover, the computer-implemented method further includes: computing, by the computer and using the information, data describing a lateral writing position to use during writing such that shingled track edges are aligned according to a format in response to determining that the difference between the information and corresponding design values is not in the range.