面向设备直通的高效低延时的中断直通方法  

An efficient and low-latency interrupt passthrough method based on device passthrough

作　　者：吕晨[1,2,3] 张福新 朱琛[4] 毛碧波 邓平科 潘筱涵 LV Chen;ZHANG Fuxin;ZHU Chen;MAO Bibo;DENG Pingke;PAN Xiaohan(State Key Laboratory of Processors,Institute of Computing Technology,Chinese Academy of Sciences,Beijing 100190;Institute of Computing Technology,Chinese Academy of Sciences,Beijing 100190;University of Chinese Academy of Sciences,Beijing 100049;Loongson Technology Corporation Limited,Beijing 100190;China Mobile Communications Corporation Research Institute,Beijing 100032)

机构地区：[1]处理器芯片全国重点实验室(中国科学院计算技术研究所),北京100190 [2]中国科学院计算技术研究所,北京100190 [3]中国科学院大学,北京100049 [4]龙芯中科技术股份有限公司,北京100190 [5]中国移动通信有限公司研究院,北京100032

出　　处：《高技术通讯》2024年第8期842-853,共12页Chinese High Technology Letters

基　　金：中国科学院计算所-中国移动研究院联合创新平台(E351500000)资助项目。

摘　　要：针对对称多处理器(SMP)虚拟机(VM)的虚拟中央处理器(vCPU)调度延迟会降低虚拟机输入/输出(I/O)响应性的问题,本文基于设备直通提出了一种高效低延迟的中断直通方法。该方法基于硬件辅助技术,搭建了中断直通架构,并设计了中断重定向机制,将直通设备中断从被抢占的vCPU重定向至正在运行的vCPU。实验结果表明,网络往返时延平均减少了34.1%,吞吐量最高提升7.9%,Apache测试每个服务器请求所需时间平均减少了13.6%,磁盘I/O操作时延平均减少了6.7%~8.4%。实验结果证明,该方法能有效减少虚拟机虚拟CPU调度对I/O延迟的影响,提高虚拟机I/O响应性。Aiming at the problem that the virtual central processing unit(CPU)scheduling delay of symmetric multi-processing(SMP)virtual machine(VM)will reduce the virtual machine input/output(I/O)responsiveness,an efficient and low-latency interrupt passthrough method based on device passthrough is proposed in this paper.Based on hardware-assisted technology,this method builds an interrupt pass-through architecture,and designs an interrupt redirection mechanism to redirect interrupts from the preempted vCPUs to running ones.The experimental results show that the round-trip time of the network is reduced by an average of 34.1%,the throughput is increased by up to 7.9%,and the time required for each server request with Apache test is reduced by an average of 13.6%,and the average latency of disk I/O operations is reduced by 6.7%~8.4%.The experimental results demonstrate that this method can effectively reduce the impact of virtual machine vCPU scheduling on I/O latency and improve virtual machine I/O responsiveness.

关 键 词：中断重映射 输入/输出(I/O)虚拟化 设备直通 基于内核的虚拟机(KVM) I/O响应性 

分 类 号：TP302[自动化与计算机技术—计算机系统结构]