Research And Implementation Of Rapid Interrupt Response Technology Based On Xen Virtualization Platform

In recent days,along with the rapid development of computer technology,distributed computing and cloud computing are spring up and widely used.As the basis to support these platform,virtualization technology can save hardware cost,enhance the security of system and is convenient to manage and maintain,thus has attracted more and more attention.Among lots of virtual productions,the open-source program Xen is a representative one,which is an implementation of para-virtualization.Xen is an open-source virtual machine monitor with high performance.It can supply a safety environment to manage resource and a new way to manage resource,giving the way to share the hardware resource among multiple operating systems.At present,Xen has gained great acceptance in the server and cloud computing arena.In recent years,it has also been widely applied to real-time embedded system with stringent timing constraints.Compared to the conventional application domain of enterprise systems,virtualization in embedded systems place strong emphasis on issues like real-time performance,but current virtualization technology is paying more attention on the justice among virtual machines,which lead to the negligence of real time requests from embedded system.So we need to modify the virtualization platform to make it a better support for real time tasks.As we all know,real time tasks usually have more interaction with hardware equipment,which can only be achieved by interrupt.So our main goal is to propose a rapid interrupt response mechanism based on Xen.We did our research on three aspects.First,by reading a large number of essays,we learned the device driver model and interrupt handling process of Xen virtualization platform,and chose the drive model that our institute to base on.Then we studied a large number of existing researches,and analyzed the real-time performance problems of current virtual machine scheduling algorithm of Xen.Finally,aimed at solving these problems,we did improvements on scheduling strategy.We put forward the concept of virtual machine real-time priority,and based on this,we did real-time performance optimization,and formed the new scheduler based on credit scheduling algorithm named credit3.We implemented the new scheduler into Xen system and the performance test shows that our strategy significantly improves the real-time performance of virtual machine.