Patent classifications
G11B20/12
Method of writing file onto tape
An approach to reducing overhead to enable high-speed writing even when a large number of small-sized files are written onto a tape in a file system. The method of the present invention includes the steps of: writing multiple files consecutively onto a tape to become one combined file; writing, onto the tape, first index information including the start position and size of the combined file on the tape; and writing, onto the tape, second index information including the start position and size of each of the multiple files in the combined file on the tape.
Shingled magnetic recording trim operation
Implementations disclosed herein include a method comprising receiving a TRIM request for a media cache in a storage media from a host, determining whether a TRIM range in the TRIM request overlaps with an active operation, invalidating the TRIM range responsive to determining that the TRIM range does not overlap with an active operation, and inserting at least one null node in the media cache. The method may comprise receiving a host read request, performing a media cache search for a read LBA range, and determining where data is located. If all the data is located in the media cache, the system reads from the media cache. If the data is located in a null node, patterning for the null node occurs. If the data is located partially in the main store, the media cache, or a null node, the data may be read, combined, and returned to the host.
System and method for multiscreen network digital video recording using on-demand transcoding
A method is disclosed that includes: receiving, via a network digital video recorder, a request to record requested content; receiving, via a network digital video recorder at a first time, the requested content in a first format and the requested content in a second format; storing, via the network digital video recorder, the requested content in the first format; storing, via the network digital video recorder, the requested content in the second format; deleting, from network digital video recorder, the requested content in the second format after a predetermined time period; and transcoding, via an on demand transcoder, the requested content in the first format to the requested content in a third format after the predetermined time period.
Aligned shingled writing for magnetic recording media and media having shingle edge positioned tracks
A computer program product, according to one embodiment, includes a computer readable storage medium having program instructions embodied therewith. The computer readable storage medium is not a transitory signal per se. Moreover, the program instructions readable and/or executable by a controller to cause the controller to perform a method which includes: determining, by the controller, whether a difference between information and corresponding design values is in a range; and computing, by the controller 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. The information corresponds to how an array of writers write and/or are expected to write to a magnetic medium during shingled recording.
Recording medium, playback device, and playback method
Data including a digital stream file obtained by encoding video information is recorded in a recording medium. A recording region of the recording medium has a first recording region where reading is performed at a first read rate, and a second recording region where reading is performed at a second read rate that is faster than the first read rate. The data includes a digital stream file having real-time attributes and a data file having non-real-time attributes. The data file to be read in during playback of the digital stream file is recorded in, of the first recording region and the second recording region, the same recording region where the digital stream file being played is recorded.
Measurement and correction of magnetic writer offset error
A method, according to one embodiment, includes writing a plurality of shingled tracks using an array of writers. The array of readers is repositioned to various locations between first and second positions and data is read from the shingled tracks at the various locations. A read offset point where read performance is about the highest during the reading performed when repositioning the array of readers between the first and second positions is determined. The method includes computing, using the read offset point, data describing a lateral writing position to use during writing such that shingled tracks are written in a location specified by a format. As a result, methods according to the present embodiment are able to provide desirable track alignment and reduced readback error rates for data of shingled tracks written to magnetic medium.
System and method for tape layout optimization
A tape layout module for determining a tape layout allocation strategy for laying out data on tape, the data being organized into a plurality of fixed-size subdata sets with each of the plurality of subdata sets including a plurality of codeword interleaves, the tape including a plurality of media defect characteristics, includes a tape layout optimization system including a processor that receives information on the plurality of media defect characteristics. The tape layout optimization system determines the tape layout allocation strategy based at least in part on at least one of the plurality of media defect characteristics. Additionally, the tape layout optimization system can determine the tape layout allocation strategy further based on distance spectra between pairs of the plurality of codeword interleaves. Further, the tape layout optimization system can determine the tape layout allocation strategy by selectively utilizing at least one tape layout parameter.
Shingled Magnetic Recording with Operational Based Track Spacing
A data storage device can employ shingled magnetic recording with data tracks oriented in order to optimize operational parameters, such as bit error rate. A data storage device can consist of a plurality of data tracks overlapping in a band on a data storage medium. First, second, and third data tracks of the band can be respectively separated by a uniform first track pitch during testing the band for an operational parameter. The first track pitch may then be adjusted to provide at least two different adjusted track pitches with each track pitch measured between longitudinal centerlines of adjacent data tracks of the band.
Method and apparatus for determining read-head deviation using orthogonal preambles
In a storage device, data is written to tracks on a storage medium. Data for each track includes a preamble. The preamble in any current track is orthogonal to the preamble in any track adjacent to the current track. A first read head is positioned over the current track and off-center toward a first adjacent track on a first side of the current track to detect first signals from among the current track, the first adjacent track, and a second adjacent track on a second side of the current track. A second read head is positioned over the current track and off-center relative to the current track toward the second adjacent track to detect second signals from among the current track, the first adjacent track, and the second adjacent track. Analyzing the first and second signals determines an amount by which the read heads are off-track from the current track.
Optical disk, optical disk recording device, and optical disk playback device
An optical disk includes a disk management information area in which predetermined information is recorded in advance, and a recording system area in which information for identifying a recording system of the optical disk recorded in a predetermined position within a non-data area included in a recordable area is recorded. A method for accessing the optical disk is decided based on disk management information and the information for identifying a recording system.