Multiple computer system using I/O port adaptor to selectively route transaction packets to host or shared I/O device

摘要

In a computer system of the present invention, CPUs of a single or a plurality of host computers access the shared IO devices connected to a shared IO bus of each shared IO device in the same manner as the host IO device in each host computer connected to the host IO bus. Each of the CPUs selects one of the host IO devices and shared IO devices by IO addressing to issue a transaction; each of the IO host adaptors gives the transaction a host number when the transaction is issued to each of the shared IO devices; and an IO port adaptor analyzes the host number of the transaction issued for each of the IO devices to decide to return said transaction to which of the plurality of host computers.