| 摘要 |
A method and apparatus for I/O forwarding in a cache coherent shared disk computer system is provided. According to the method, a requesting node transmits a request for requested data to a managing node. The managing node receives the read request from the requesting node and grants a lock on the requested data. Th e managing node then forwards data that identifies the requested data to a dis k controller. The disk controller receives the data that identifies the requested data fro m the managing node and reads a data item, based on the data that identifies the requested data, from a shared disk. After reading the data item from the shared disk, the disk controller transmits the data item to the requesting node. In one embodiment, an I/O destination handle is generated that identifies a read request and a buffer cache addres s to which the data item should be copied. The I/O destination handle is transmitted to the disk controller to facilitate transmission and processing of the data item from t he disk controller to the requesting node. As a result of forwarding data that identifies the requested data directly from the managing node to the disk controller ("I/O forwarding"), the duration of a stall is reduced, contention on resources of the system is reduced and a context switch is eliminated.
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