Abstract: According to one embodiment, a magnetic recording medium includes: a substrate; an underlayer positioned above the substrate; a magnetic recording layer positioned above the underlayer; and a plurality of conductive polymers dispersed within the substrate, the underlayer, the magnetic recording layer, the substrate and the underlayer, the substrate and the magnetic recording layer, the underlayer and the magnetic recording layer, or the underlayer, the magnetic recording layer, and the substrate. In addition, the conductive polymers are dispersed such that a concentration of the conductive polymers has a gradient in a single one of the layers in a thickness direction.

Abstract: 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.

Abstract: A computer-implemented method according to one embodiment includes sending a data request from a host to a storage drive, where the data request includes quality of service (QoS) information, receiving, in response to the data request, a response from the storage drive at the host, and performing one or more actions at the host, based on the response.

Abstract: A computer-implemented method according to one embodiment includes receiving at a storage drive, from a host, a data request, implementing the data request at the storage drive, utilizing a streaming mode, and returning, by the storage drive, a confirmation to the host, in response to implementing the data request at the storage drive utilizing the streaming mode.

Abstract: A computer-implemented method according to one embodiment includes sending, from a host to a storage drive, a read request for data, receiving, at the host from the storage drive, a portion of the data as fixed-size two-dimensional units, where the fixed-size two-dimensional units are mapped to fixed-size one-dimensional user data blocks located at the host, and performing one or more actions at the host, utilizing the portion of the data.

Abstract: In one general embodiment, a method includes receiving data logically organized into a predetermined number of two-dimensional arrays, each two-dimensional array including a plurality of NS codewords positioned orthogonally to a plurality of WS codewords. The method also includes successively writing each of the NS codewords to a data storage medium. A first NS codeword from a first two-dimensional array is written to the data storage medium prior to starting to write a second NS codeword from the first two-dimensional array. Also, the plurality of NS codewords are protected with a stronger encoding than the plurality of WS codewords.

Abstract: A method of operating a magnetic tape within a tape drive. The tape drive comprises a tape head, which shows a tape-bearing surface meant to face a front side of a magnetic tape, in operation. The tape-bearing surface comprises a transducer area. This area includes at least one transducer, which is a read or write element configured to read or write to the magnetic tape, respectively. The method may include driving the tape (along a longitudinal direction of circulation thereof above the tape-bearing surface) and concomitantly ejecting a gas flow toward the transducer area. The gas flow ejected impinges on the back side of the driven tape (e.g., opposite to the front side of the tape), so as to locally urge the front side of the tape against the transducer area and thereby read or write to the tape via said at least one transducer.

Abstract: An apparatus according to one embodiment includes a plurality of first modules each having a first write transducer. The apparatus further includes a plurality of second modules each having a second write transducer. Planes of deposition of write gaps of the second write transducers are oriented at an angle of greater than 4 degrees relative to planes of deposition of write gaps of the first write transducers. The media bearing surfaces of the modules are primarily planar, and lie along offset parallel planes. An apparatus according to another embodiment includes a first module having a plurality of first write transducers. The apparatus further includes a second module having a plurality of second write transducers. Planes of deposition of write gaps of the second write transducers are oriented at an angle of greater than 4 degrees relative to planes of deposition of write gaps of the first write transducers.

Abstract: 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.

Abstract: A computer-implemented method according to one embodiment includes identifying code word interleaved (CWI)-4 entries to be re-written to a data storage cartridge, selecting a subset of the CWI-4 entries to be included within a first CWI-4 set, where a plurality of the CWI-4 entries within the subset are associated with a single sub data set (SDS), and re-writing the first CWI-4 set to the data storage cartridge.

Abstract: A determination is made whether read/write is enabled within the tape drive storage unit. In response to determining that read/write is enabled, a determination is made whether a temperature within the tape drive storage unit exceeds a threshold value. In response to determining that the temperature within the tape drive storage unit exceeds the threshold value, a determination is made of a direction of travel of a tape media within the tape drive storage unit. In response to determining that the direction of travel is a forward direction, a first cooling device is powered on. The first cooling device lowers the temperature of a first guide roller and the tape media coming off a first tape storage reel prior to the tape media passing by a read/write head within the tape drive storage unit.

Abstract: Predictively selecting subset of disks of a storage system to be spun-up, including providing metadata of data entities stored in the disks of the storage system, estimating the data entity access probabilities for a prediction time window based on the metadata, each data entity access probability being indicative for the probability of access to a certain data entity within the prediction time window, calculating disk access probabilities for a prediction time window based on the estimated probability of access of data entities, each disk access probability being indicative for the probability of access to a certain disk within the prediction time window, estimating the number of disks to be spun-up in a certain prediction time window, dynamically adapting the data entity threshold value and/or the disk access threshold value, selecting a subset of disks to be spun-up in the following prediction time window.

Abstract: A method according to one embodiment includes applying a static head skew to a magnetic tape head, positioning the first reader at a first y-position relative to a servo pattern in a servo band, and measuring y-positions of the second reader relative to the servo pattern in the servo band while the first reader is at the first y-position. A y-position value is calculated for the second reader based on the measured y-positions. The following process is repeated several times: moving the first reader to a next y-position, measuring y-positions of the second reader while the first reader is at the next y-position, and calculating a y-position value of the second reader based on the measured y-position of the second reader. A unique nonlinearity value of the servo pattern in the servo band is calculated for each of the calculated y-position values of the second reader.

Abstract: A method according to one embodiment includes generating a y-position estimate based on a servo readback signal, and determining a nonlinearity-correction value corresponding to the y-position estimate. The method further includes adjusting the y-position estimate using the nonlinearity-correction value. A computer program product for compensating for nonlinearity in a timing based servo pattern according to another embodiment includes a computer readable storage medium having program instructions embodied therewith. The program instructions are readable and/or executable by a controller to cause the controller to perform the foregoing method. An apparatus according to another embodiment includes a controller configured to perform the foregoing method.

Abstract: A computer-implemented method according to one embodiment includes sending, from a host to a storage drive, a read request for data, receiving, at the host from the storage drive, a portion of the data as fixed-size two-dimensional units, where the fixed-size two-dimensional units are mapped to fixed-size one-dimensional user data blocks located at the host, and performing one or more actions at the host, utilizing the portion of the data.

Abstract: A computer-implemented method according to one embodiment includes sending a data request from a host to a storage drive, where the data request includes quality of service (QoS) information, receiving, in response to the data request, a response from the storage drive at the host, and performing one or more actions at the host, based on the response.

Abstract: A computer-implemented method according to one embodiment includes receiving at a storage drive, from a host, a data request, implementing the data request at the storage drive, utilizing a streaming mode, and returning, by the storage drive, a confirmation to the host, in response to implementing the data request at the storage drive utilizing the streaming mode.

Abstract: A computer-implemented method is provided for managing digital datasets stored on a multi-tiered storage system that includes several tiers of storage, the datasets likely to be accessed by one or more applications interacting with the storage system. The method includes monitoring an access history of datasets accessed by the one or more applications; and while monitoring the access history: computing probabilities of access, by the one or more applications, of the datasets stored on the storage system according to metadata associated to given datasets as identified in the monitored access history; and based on the computed probabilities of access, selecting one or more of the datasets to be moved across the tiers. Related storage systems and computer program products are also provided.

Abstract: A system includes, according to one embodiment, a magnetic head having a plurality of write transducers configured to store data to tracks of a sequential access medium and a plurality of read transducers. Each read transducer is configured to read data from the sequential access medium after being written thereto by a corresponding write transducer. A first of the read transducers is aligned with a first of the write transducers, wherein the output of the first read transducer is produced during read-while-write. The system also includes a controller and logic integrated with and/or executable by the controller. The logic is configured to read, using the plurality of read transducers, encoded data from a plurality of tracks of the sequential access medium simultaneously.

Abstract: The invention is notably directed to computer-implemented methods and systems for managing datasets in a storage system. In such systems, it is assumed that a (typically small) subset of datasets are labeled with respect to their relevance, so as to be associated with respective relevance values. Essentially, the present methods determine, for each unlabeled dataset of the datasets, a respective probability distribution over a set of relevance values. From this probability distribution, a corresponding relevance value can be obtained. This probability distribution is computed based on distances (or similarities), in terms of metadata values, between said each unlabeled dataset and the labeled datasets. Based on their associated relevance values, datasets can then be efficiently managed in a storage system.