发明授权
- 专利标题: Method for implementing point-in-time copy using a snapshot function
- 专利标题(中): 使用快照功能实现时间点复制的方法
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申请号: US09006548申请日: 1998-01-13
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公开(公告)号: US06212531B1公开(公告)日: 2001-04-03
- 发明人: David Randall Blea , Donald Reynold Blea , Mark Alan Haye , Ronald Maynard Kern , David M. Shackelford , John G. Thompson
- 申请人: David Randall Blea , Donald Reynold Blea , Mark Alan Haye , Ronald Maynard Kern , David M. Shackelford , John G. Thompson
- 主分类号: G06F1730
- IPC分类号: G06F1730
摘要:
A method, apparatus, and article of manufacture for performing a point-in-time backup using a snapshot function. Work space on a work virtual volume is obtained to hold the snapshot copy of the source data being copied from a source virtual volume. Updates to the source virtual volume are suspended during the snapshot function, so as to provide a logically consistent view of the source virtual volume at a common point in time. Pointers are copied from a virtual track table of the source virtual volume to a virtual track table of the work virtual volume without actually moving any data on data storage devices referenced by those pointers. As a result, the snapshot function provides a method for copying the source virtual volume to the work virtual volume very quickly. Upon completion of the snapshot function, updates to the source virtual volume may be resumed. Subsequently, a backup is performed in the usual manner, except that the backup retrieves the source data from the work virtual volume rather than the source virtual volume.