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Nearline storage (a portmanteau of "near" and "online storage") is a term used in computer science to describe an intermediate type of data storage that represents a compromise between online storage (supporting frequent, very rapid access to data) and offline storage/archiving (used for backups or long-term storage, with infrequent access to data).〔("Nearline storage" ) in ("A Glossary of Archival and Records Terminology" ). Retrieved on 2009-01-30.〕〔Venkatramani, Chitra and Tzi-cker Chiueh (1993). ("Survey of Near-Line Storage Technologies: Devices and Systems" ). Experimental Computer Systems Laboratory.〕 Nearline storage dates back to the IBM 3850 Mass Storage System (MSS) tape library, which was announced in 1974.〔 == Overview == The formal distinction between online, nearline, and offline storage is:〔 * Online storage is immediately available for I/O. * Nearline storage is not immediately available, but can be made online quickly without human intervention. * Offline storage is not immediately available, and requires some human intervention to become online. For example, always-on spinning hard disk drives are online storage, while spinning drives that spin down automatically, such as in massive arrays of idle disks (MAID), are nearline storage. Removable media such as tape cartridges that can be automatically loaded, as in tape libraries, are nearline storage, while tape cartridges that must be manually loaded are offline storage. 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「Nearline storage」の詳細全文を読む スポンサード リンク
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