面向存储网络的融合I/O模拟器设计与实现

Network and storage oriented converged I/O device simulator

在现有计算机系统结构中,要实现跨节点的数据存储操作,数据需要先经过本地网卡、远程网卡、远程内存才能到达远程存储设备。这一过程通常还需要远程节点操作系统和应用软件的参与才能完成。随着硬件技术的发展,存储设备的访问延迟大幅下降。为了进一步降低节点数据传输延迟,充分发挥存储设备的性能优势,本文设计了面向网络与存储的融合I/O设备模型UIO,通过让多个功能模块共享存储设备中的内存和数据通路,以简化跨节点数据存储的传输通路优化。并加入辅助计算功能实现数据处理操作,通过与可编程硬件的结合,可以让用户定制辅助计算模块,提高UIO设备的处理效率,扩展应用场景。设计并实现了面向key-value存储系统的UIO设备模拟器,使用4 kB长度value的情况下,与传统数据通路对比,远程put延迟可以降低31%,远程get延迟减少20%。综合指令延迟和指令使用频率对整体操作延迟进行分析,UIO设备在目标场景中预期可以达到比传统数据通路更低的延迟。

In the existing computer system architecture,to achieve cross-node data storage operations,data often need to go through the local network card,remote network card and remote memory to reach the remote storage device.This process often requires the participation of remote node operating system and applications.With the development of hardware technology,storage equipment access delay is greatly reduced.In order to further reduce the delay of data transmission across nodes and give full play to the performance advantages of new storage devices,this paper designs a network and storage oriented converged I/O device model UIO to simplify the transmission path of cross-node data storage.The UIO device converges storage and network functions in the same device,reducing the data transmission delay by allowing multiple functional blocks to share memory and data paths in the device to simplify the data transmission path.The UIO device model implements the data processing operations by adding the auxiliary calculation function to the device.Through the combination with the programmable hardware,allowing users to customize the auxiliary calculation modules improves the processing efficiency of UIO devices and expands its application scenarios.This work designs and implements a UIO device simulator for a key-value storage system to verify the effect of the UIO device model.In the simulation test,the remote put delay can be reduced by 31%compared to the traditional data path in the case of 4 kB value,and the remote get delay can be reduced by 20%.