公开(公告)号：US07571293B1

公开(公告)日：2009-08-04

申请号：US11472685

申请日：2006-06-22

申请人： Douglas E. LeCrone ,  Bruce Alan Pocock ,  Paul Linstead ,  Roger A. Ouellette

发明人： Douglas E. LeCrone ,  Bruce Alan Pocock ,  Paul Linstead ,  Roger A. Ouellette

IPC分类号： G06F13/00 ,  G06F13/28 ,  G06F9/455

CPC分类号： G06F13/105 ,  G06F3/0607 ,  G06F3/065 ,  G06F3/0661 ,  G06F3/0683

摘要： A host computer system (host) includes an application that generates I/O commands for a first type of point-in-time (PIT) copy operation, and an I/O subsystem coupled to a data storage system capable of performing a second type of PIT copy operation. The host processes the I/O commands as part of an emulation of the first type of PIT copy operation, including determining whether the I/O commands require modification for the emulation, and if so whether they are of a back-end type or an out-of-band type. The I/O commands that do not require modification are processed without modification via the I/O subsystem. For the back-end I/O commands, (i) an intercept condition is set, (ii) the I/O commands are processed via the I/O subsystem, and (iii) upon completion with the intercept condition set, the results are modified so as to indicate to the application that the first type of PIT copy operation can be performed on the storage volumes. For the out-of-band I/O commands, (i) corresponding commands of the second type of PIT copy operation are processed via the I/O subsystem in lieu of the out-of-band I/O commands, and (ii) upon completion of the substituted I/O commands, corresponding results are returned to the application as though the out-of-band I/O commands had been processed by the I/O subsystem. Using this technique, a host that initiates only PIT copying operations of the first type can be used with storage systems that support second-type PIT copying operations.

摘要翻译： 主计算机系统（主机）包括生成用于第一类型时间点（PIT）复制操作的I / O命令的应用程序，以及耦合到能够执行第二类型的数据存储系统的I / O子系统 的PIT复制操作。 主机处理I / O命令作为第一类PIT复制操作的仿真的一部分，包括确定I / O命令是否需要对仿真进行修改，如果是这样，它们是否为后端类型或 带外类型。 不需要修改的I / O命令通过I / O子系统进行处理，无需修改。 对于后端I / O命令，（i）设置了截取条件，（ii）I / O命令通过I / O子系统进行处理，（iii）在完成了拦截条件设置后，结果 被修改为向应用指示可以对存储卷执行第一类型的PIT复制操作。 对于带外I / O命令，（i）通过I / O子系统处理第二类PIT复制操作的相应命令，代替带外I / O命令，（ii） ）在完成替换的I / O命令后，相应的结果将返回给应用程序，就像I / O子系统已经处理了带外I / O命令一样。 使用这种技术，只能启动第一类型的PIT复制操作的主机可以与支持第二类型PIT复制操作的存储系统一起使用。