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The IBM 3570 is a series of tape drives and corresponding magnetic tape data storage media formats developed by IBM. The storage technology and media were introduced using the name Magstar MP, combining the IBM storage brand name ''Magstar'' with ''MP'' for MultiPurpose. The IBM product number 3570 was associated with the tape drives and libraries that used the Magstar MP media. The IBM 3570 technology was specifically produced for mid-range computer systems, and for the tape cartridges to be primarily stored in and handled by automated tape libraries. The technology was specifically designed for fastest access to the data, with quick robotic tape loading and near-instant head to tape contact in mid-tape after loading.〔 However, slower tape technologies with higher per-tape capacities proved more successful in the marketplace, and the IBM 3570 technology did not enjoy a large market penetration. == Technology == The IBM Magstar MP technology is a compact tape technology using a small dual-reel tape cartridge which was introduced in September, 1996. The key design points of this technology are: * Fast access to data through quick tape load/unload cycle times, and a mid-tape load-point design * High reliability of media and cartridges under heavy duty read and write loads * Heavy use of automated libraries for tape handling * High performance in a mid-range computing environment The technology was upgraded in 1998 to increase both capacity and performance. This tape format is based on an 8mm tape with 128 tracks arranged in an interleaved longitudinal serpentine format. The tapes used a metal particle technology, and the tape drives used a magneto-resistive head technology, with LZ1 data compression built into the drive. An unusual feature is the mid-tape load-point. In contrast, most tape technologies view a tape as a linear length, similar to an audio cassette. Normally, a tape load is completed by spooling past the head to an initial load-point at one end of the tape, while forward tape motion brings the head closer towards the end-of-tape/end-of-track in a linear fashion. IBM chose a different approach, placing the start-of-tape initial load-in point halfway along the tape's length. Relative to the centre load-point, tracks run both backwards and forwards towards each end of the tape. This improves average access times, with a worst-case seek request needing spool through only a maximum of half the tape's length. In comparison, traditional formats may need to spool through the full tape length, doubling the time-to-seek of IBM's product. This family of drives, alongside the StorageTek 9840, may be the only modern tape storage products taking this mid-tape load-point approach. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「IBM Magstar MP 3570」の詳細全文を読む スポンサード リンク
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