基于虚拟化环境下SSD性能优化机制研究
发布时间：2018-08-03 18:12
【摘要】：在虚拟化环境下，通过改变底层的存储硬件可以大幅提升虚拟机读写性能及效率。固态硬盘（SSD）与传统的机械硬盘相比，具有低延时，低能耗，高吞吐率，高带宽等众多优势。但需要注意的是，在虚拟化环境下引入SSD并不是简单的物理替换，由于其自身的结构和特点，使得SSD的重要设备指令trim不能通过虚拟机传递至底层的SSD，从而引起了SSD使用性能的严重下降。因此，如何打破虚拟机与底层硬件的语义鸿沟，在引入SSD后准确的将trim指令传递至底层硬件，成为亟待解决的问题。 虚拟化环境下引入SSD的优化系统Vtrim（trim for Virtual Block Devices）可以实时将trim指令传递至底层的SSD。trim指令需要经由操作系统的删除操作进行触发，但在虚拟机中的删除操作由于虚拟化语义鸿沟的存在无法触发trim指令。针对这种情况，，Vtrim系统将虚拟机中的删除操作进行实时的监控。当虚拟机文件要被删除时，Vtrim系统截获这种行为并实时的将删除语义传至虚拟机管理域（domain0），而后将虚拟机中的删除行为在domain0中进行相应的语义解析。解析语义完毕后，将会获得对应虚拟机磁盘镜像文件上所需要删除的位置及删除长度，利用domain0的删除操作可以触发trim指令的特点，在domain0中将虚拟机磁盘镜像上需要删除的部分使用文件打洞的方式进行删除，从而触发trim指令，实现了SSD在虚拟化环境下的性能的优化。 功能测试证明，Vtrim可以在虚拟机运行的情况下，实时的截获、传递、解析、并在本地执行删除操作，有效的将trim指令传递至底层SSD的主控中。性能分析证明，针对使用半虚拟化的虚拟机而言，使用Vtrim进行长期优化的虚拟机，相比长期未优化的虚拟机来说，虚拟机磁盘随机写性能最大可提高将近150%，平均响应时延最大可减少至原来的40%左右。
[Abstract]:In virtualized environment, the performance and efficiency of virtual machine reading and writing can be greatly improved by changing the underlying storage hardware. Compared with traditional mechanical hard disk, (SSD) has many advantages, such as low delay, low energy consumption, high throughput and high bandwidth. However, it is important to note that the introduction of SSD in a virtualized environment is not a simple physical replacement, because of its own structure and characteristics, The important device instruction trim of SSD can not be passed through virtual machine to the underlying SSDs, which results in a serious deterioration of SSD performance. Therefore, how to break the semantic gap between the virtual machine and the underlying hardware and accurately transfer the trim instructions to the underlying hardware after the introduction of SSD has become an urgent problem to be solved. Vtrim (trim for Virtual Block Devices), an optimization system that introduces SSD into virtualization environment, can transfer trim instructions to the underlying SSD.trim instructions in real time, which need to be triggered by the delete operation of the operating system. However, the delete operation in virtual machine can not trigger the trim instruction because of the semantic gap of virtualization. In this case, the Vtrim system monitors the delete operation in the virtual machine in real time. When the virtual machine file is to be deleted, the Vtrim system intercepts this behavior and transmits the deletion semantics to the virtual machine management domain (domain0) in real time. Then the delete behavior in the virtual machine is parsed in the domain0. After parsing the semantics, the location and length of deletion needed to be deleted on the corresponding virtual machine disk image file will be obtained. The deletion operation of domain0 can trigger the characteristics of the trim instruction. In domain0, some parts of virtual machine disk image that need to be deleted are deleted by the way of file hole, which triggers the trim instruction, and realizes the optimization of the performance of SSD in the virtualization environment. The function test shows that Vtrim can intercept, transfer, parse and delete the trim instructions in real time when the virtual machine is running, and effectively transfer the trim instructions to the master control of the underlying SSD. Performance analysis shows that for virtual machines with paravirtualization, virtual machines with Vtrim for long-term optimization, compared with long-unoptimized virtual machines, The maximum random write performance of virtual machine disk can be improved by nearly 150 and the average response delay can be reduced to about 40%.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TP333.35
本文编号：2162554
[Abstract]:In virtualized environment, the performance and efficiency of virtual machine reading and writing can be greatly improved by changing the underlying storage hardware. Compared with traditional mechanical hard disk, (SSD) has many advantages, such as low delay, low energy consumption, high throughput and high bandwidth. However, it is important to note that the introduction of SSD in a virtualized environment is not a simple physical replacement, because of its own structure and characteristics, The important device instruction trim of SSD can not be passed through virtual machine to the underlying SSDs, which results in a serious deterioration of SSD performance. Therefore, how to break the semantic gap between the virtual machine and the underlying hardware and accurately transfer the trim instructions to the underlying hardware after the introduction of SSD has become an urgent problem to be solved. Vtrim (trim for Virtual Block Devices), an optimization system that introduces SSD into virtualization environment, can transfer trim instructions to the underlying SSD.trim instructions in real time, which need to be triggered by the delete operation of the operating system. However, the delete operation in virtual machine can not trigger the trim instruction because of the semantic gap of virtualization. In this case, the Vtrim system monitors the delete operation in the virtual machine in real time. When the virtual machine file is to be deleted, the Vtrim system intercepts this behavior and transmits the deletion semantics to the virtual machine management domain (domain0) in real time. Then the delete behavior in the virtual machine is parsed in the domain0. After parsing the semantics, the location and length of deletion needed to be deleted on the corresponding virtual machine disk image file will be obtained. The deletion operation of domain0 can trigger the characteristics of the trim instruction. In domain0, some parts of virtual machine disk image that need to be deleted are deleted by the way of file hole, which triggers the trim instruction, and realizes the optimization of the performance of SSD in the virtualization environment. The function test shows that Vtrim can intercept, transfer, parse and delete the trim instructions in real time when the virtual machine is running, and effectively transfer the trim instructions to the master control of the underlying SSD. Performance analysis shows that for virtual machines with paravirtualization, virtual machines with Vtrim for long-term optimization, compared with long-unoptimized virtual machines, The maximum random write performance of virtual machine disk can be improved by nearly 150 and the average response delay can be reduced to about 40%.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TP333.35
【参考文献】
相关期刊论文 前1条
1 吴佩贤;Linux环境下基于TCP的Socket编程浅析[J];现代电子技术;2005年16期
相关硕士学位论文 前1条
1 汤泉;基于文件的Xen虚拟磁盘研究[D];上海交通大学;2008年
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