Research And Design On I/O Emulation Technology With X86 Architecture

System emulation is a sub item of the architecture migration. It is a kind of method, which can ignore the difference of architecture, support the compatibility of software, resist the attack from network, restore the data quickly from balefulness, and reduce the cost of software and hardware. The importance of system emulation is being taken more and more attention from the domain of the study, manufacture and appliance. As the development of architecture and contact of the I/O technology, I/O emulation suffers low performance. Device direct contact, paravirtualization, software emulation, device balloon model and much technology give more reference for the I/O emulation. This thesis focuses on the key technology of the I/O emulation, and the main work and research results are as follows:This thesis analyzed the implement technology and device model, compared the advantage and disadvantage of all the kinds of device emulation technology and proposes a kind of I/O architecture named ABIO based on scan and transmission, describing the blue print of ABIO from function module, interface technology and working flow. The thesis designed and emulated the PCI bus architecture, which take the PCI bus architecture, interrupt system, timer system as the emulated target illustrate the course of the emulation. After that the thesis designed and emulated the disk device based on the scan and transmission, analyzing the design of the module, emulation code architecture, working flow. Based on the analyzing of the I/O emulation principle, ABIO possesses the function of universality, practicability and customization; it achieved the requirement from X86 platform, multiple architecture and customer.According to the design and emulation above, this thesis took a test on the disk I/O and ABIO by using VDT and Bonnie++. The result shows that compared to the QEMU, the performance of the disk device based on the Pass-through has been improved by 4.25%-29.3%. The result of Bonnie++ shows that compared to the QEMU, the performance of ABIO has been improved 4.22%-31.32%, compared to the Bochs, the performance of ABIO has been improved 12.25%-28.81%. So the ABIO can improved the performance of the system emulation, but it should be studied deeply, to make more optimization.