A magnetic tape device, a magnetic tape, and a magnetic tape cartridge, in which the magnetic tape is caused to run between a winding reel and a cartridge reel in a state where a tension is applied in a longitudinal direction of the magnetic tape and a maximum value of the tension is 0.50 N or more, the magnetic tape after running in a state where the tension is applied is wound around the cartridge reel by applying a tension of 0.40 N or less in the longitudinal direction, and a center line average roughness Ra measured regarding a surface of a back coating layer of the magnetic tape with an atomic force microscope is in a range of 5 to 13 nm.

An approach for improving the tape storage media by optimizing tape drives in a tape library. Embodiments manage, by a web interface provided by a tape library, an inventory of one or more tape drives and the one or more tape media in the tape library, and record high tension discharge and distance measurement after formatting in a cartridge memory of the one or more tape media in the tape library. Further, embodiments manage the high tension discharge and the distance measurement after formatting in the cartridge memory of the one or more tape media by measuring a distance between servo bands utilizing one or more unused tape drives and one or more low frequency tape drives in the tape library, and execute a rewind at low tension using the one or more unused tape drive and the one or more low frequency tape drives.

An approach for improving the tape storage media by optimizing tape drives in a tape library. Embodiments manage, by a web interface provided by a tape library, an inventory of one or more tape drives and the one or more tape media in the tape library, and record high tension discharge and distance measurement after formatting in a cartridge memory of the one or more tape media in the tape library. Further, embodiments manage the high tension discharge and the distance measurement after formatting in the cartridge memory of the one or more tape media by measuring a distance between servo bands utilizing one or more unused tape drives and one or more low frequency tape drives in the tape library, and execute a rewind at low tension using the one or more unused tape drive and the one or more low frequency tape drives.

The present disclosure provides where a magnetic recording medium is provided and includes a base; an underlayer that is provided over the base and includes a non-magnetic powder; and a magnetic layer that is provided over the underlayer and includes a magnetic powder and a binder, wherein an average particle volume V of the magnetic powder is 1600 nm.sup.3 or less, an average thickness of the magnetic recording medium is 5.3 μm or less, a thermal stability K.sub.uV.sub.act/k.sub.BT of the magnetic recording medium is 63 or more, and a ratio Hrp/Hc1 of a residual coercive force Hrp of the magnetic recording medium measured using a pulsed magnetic field in a perpendicular direction to a coercive force Hc1 of the magnetic recording medium in the perpendicular direction is 1.98 or less.

The present disclosure provides where a magnetic recording medium is provided and includes a base; an underlayer that is provided over the base and includes a non-magnetic powder; and a magnetic layer that is provided over the underlayer and includes a magnetic powder and a binder, wherein an average particle volume V of the magnetic powder is 1600 nm.sup.3 or less, an average thickness of the magnetic recording medium is 5.3 μm or less, a thermal stability K.sub.uV.sub.act/k.sub.BT of the magnetic recording medium is 63 or more, and a ratio Hrp/Hc1 of a residual coercive force Hrp of the magnetic recording medium measured using a pulsed magnetic field in a perpendicular direction to a coercive force Hc1 of the magnetic recording medium in the perpendicular direction is 1.98 or less.

In the probability distribution calculated from TDSage, TDSenv, and TC, the magnetic tape has the probability P.sub.fail of equal to or less than 0.2%, in which the absolute value of ΔSB exceeds 0.3 μm. TDSage is a maximum absolute value of a difference between the servo band interval obtained before a predetermined storage and the servo band interval obtained after the storage, TDSenv is a value calculated by multiplying a difference between a maximum value and a minimum value of the servo band interval respectively obtained under five predetermined environments by ½, TC is a value calculated by multiplying TDStens by 0.5 N, and TDStens is a ratio of a change in the servo band interval to a change in tension calculated from the servo band interval respectively obtained under five predetermined environments by applying a plurality of different tensions in the longitudinal direction of the magnetic tape.

In the probability distribution calculated from TDSage, TDSenv, and TC, the magnetic tape has the probability P.sub.fail of equal to or less than 0.2%, in which the absolute value of ΔSB exceeds 0.3 μm. TDSage is a maximum absolute value of a difference between the servo band interval obtained before a predetermined storage and the servo band interval obtained after the storage, TDSenv is a value calculated by multiplying a difference between a maximum value and a minimum value of the servo band interval respectively obtained under five predetermined environments by ½, TC is a value calculated by multiplying TDStens by 0.5 N, and TDStens is a ratio of a change in the servo band interval to a change in tension calculated from the servo band interval respectively obtained under five predetermined environments by applying a plurality of different tensions in the longitudinal direction of the magnetic tape.

A computer-implemented method for indexing a tape for unmounting from a tape drive. The computer-implemented method includes: receiving a request to unmount the tape from the tape drive, wherein the tape includes an index partition and a data partition, determining that an update to the tape is not reflected in any data index written in the data partition, appending a new data index at the end of the last written data file in the data partition, wherein the new data index includes information associated with the update to the tape, unthreading the tape from the tape drive, wherein unthreading the tape from the tape drive is performed at low tension writing a metadata index to an ancillary storage device, wherein the metadata index includes information associated with the update to the tape.

A computer-implemented method for indexing a tape for unmounting from a tape drive. The computer-implemented method includes: receiving a request to unmount the tape from the tape drive, wherein the tape includes an index partition and a data partition, determining that an update to the tape is not reflected in any data index written in the data partition, appending a new data index at the end of the last written data file in the data partition, wherein the new data index includes information associated with the update to the tape, unthreading the tape from the tape drive, wherein unthreading the tape from the tape drive is performed at low tension writing a metadata index to an ancillary storage device, wherein the metadata index includes information associated with the update to the tape.

The present disclosure provides a tape-shaped magnetic recording medium, including: a base; and a magnetic layer that is provided on the base and contains a magnetic powder, in which an average particle volume V of the magnetic powder is 2,000 nm.sup.3 or less, an average thickness of the magnetic recording medium is 5.3 μm or less, a thermal stability K.sub.uV/k.sub.BT of the magnetic recording medium is 60 or more, and a ratio Hrp/Hc1 of a residual coercive force Hrp of the magnetic recording medium measured using a pulsed magnetic field to a coercive force Hc1 of the magnetic recording medium in a perpendicular direction is 2.10 or less.