Patent classifications
G11B2220/956
Magnetic tape and magnetic tape device
The magnetic tape includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which the magnetic layer has a timing-based servo pattern, a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, and an isoelectric point of a surface zeta potential of the magnetic layer is equal to or greater than 5.5.
Magnetic tape and magnetic tape device
The magnetic tape includes a non-magnetic support; a non-magnetic layer including a non-magnetic powder and a binding agent on the non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic layer, in which a total thickness of the non-magnetic layer and the magnetic layer is equal to or smaller than 0.60 μm, the magnetic layer has a servo pattern, and an isoelectric point of a surface zeta potential of the magnetic layer is equal to or greater than 5.5.
Adaptive tape calibration criteria by number of stop writes
In an approach to adaptive tape calibration criteria based on the number of stop writes, the number of rewrite occurrences caused by a stop write is determined for each specific tape drive type. Responsive to detecting a stop write during a write operation, the total number of stop writes is stored on the tape drive. A rewrite calibration threshold is determined, where the rewrite calibration threshold includes the total number of stop writes on the tape drive and a calibration reference value for the specific tape drive type. Responsive to the number of rewrite occurrences caused by the stop write exceeding the rewrite calibration threshold while writing a data set on the tape drive, a calibration of the tape drive is performed.
MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, and a magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape. In a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 5 kV, the number of bright regions having an equivalent circle diameter of 60 nm or more and less than 120 nm is 8000 or more and 30000 or less. Standard deviation σ of the number of the bright regions in a width direction of the surface of the magnetic layer is 2000 or less.
Partial reverse concatenation for data storage devices using composite codes
In one embodiment, a system includes a processor, and logic integrated with the processor, executable by the processor, or integrated with and executable by the processor. The logic is configured to cause the processor to write, by the processor, data to a storage medium of a data storage system using a partial reverse concatenated modulation code. The partial reverse concatenated modulation code comprises encoding the data by applying a C2 encoding scheme prior to encoding the data by applying one or more modulation encoding schemes, followed by encoding the data by applying a C1 encoding scheme subsequent to the encoding of the data with the one or more modulation encoding schemes.
High speed file copy from tape using block grouping
A computer-implemented method, according to one approach, includes: receiving a request to read a plurality of files from a magnetic tape, and obtaining a tape directory which identifies regions on the magnetic tape in which the files are stored. The tape directory is used to map each of the files to one of the regions on the magnetic tape in which the respective file is stored. A first subset of the files stored in a same first region on the magnetic tape is also sorted into a first order. The computer-implemented method further includes simultaneously: sorting a second subset of the files stored in a same second region on the magnetic tape into a second order, and instructing a tape drive to read each of the files in the first subset according to the first order.
Partial reverse concatenation for data storage devices using composite codes
In one embodiment, a computer program product includes a computer readable storage medium having program instructions embodied therewith. The computer readable storage medium is not a transitory signal per se. The embodied program instructions are readable/executable by a processor to cause the processor to write, by the processor, data to a storage medium of a data storage system using a partial reverse concatenated modulation code. The partial reverse concatenated modulation code includes encoding the data by applying a C2 encoding scheme prior to encoding the data by applying one or more modulation encoding schemes, followed by encoding the data by applying a C1 encoding scheme subsequent to the encoding of the data with the one or more modulation encoding schemes. Other computer program products for writing data to a storage medium of a data storage system using a partial reverse concatenated modulation code are presented according to more embodiments.
PARTIAL REVERSE CONCATENATION FOR DATA STORAGE DEVICES USING COMPOSITE CODES
In one embodiment, a system includes a processor, and logic integrated with the processor, executable by the processor, or integrated with and executable by the processor. The logic is configured to cause the processor to write, by the processor, data to a storage medium of a data storage system using a partial reverse concatenated modulation code. The partial reverse concatenated modulation code comprises encoding the data by applying a C2 encoding scheme prior to encoding the data by applying one or more modulation encoding schemes, followed by encoding the data by applying a C1 encoding scheme subsequent to the encoding of the data with the one or more modulation encoding schemes.
Magnetic tape having characterized magnetic layer surface, magnetic tape cartridge, and magnetic tape apparatus
The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, and a magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape. In a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 5 kV, the number of bright regions having an equivalent circle diameter of 60 nm or more and less than 120 nm is 8000 or more and 30000 or less. Standard deviation of the number of the bright regions in a width direction of the surface of the magnetic layer is 2000 or less.
MAGNETIC TAPE HAVING CHARACTERIZED MAGNETIC LAYER SURFACE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, and a magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape. In a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 5 kV, the number of bright regions having an equivalent circle diameter of 60 nm or more and less than 120 nm is 8000 or more and 30000 or less. Standard deviation ? of the number of the bright regions in a width direction of the surface of the magnetic layer is 2000 or less.