CSR: Small: Multi-hypervisor Virtual Machines - Enabling an Ecosystem of Hypervisors in the Cloud

现代云计算平台在操作系统、数据库系统、财务软件、虚拟网络路由器等方面为用户提供了一系列选择，所有这些都可以在虚拟机(VM)中轻松定制和执行。遗憾的是，这一级别的用户选择没有扩展到底层系统软件，称为管理程序，它使云基础设施能够运行VM。一方面，云提供商有机会通过提供丰富的管理程序级别服务(如Rootkit检测、实时修补、入侵检测、高可用性和VM自检)来实现服务差异化。另一方面，云提供商很难开发和维护一个包含每个云用户想要的所有功能的单一管理程序。本研究旨在实现一个软件生态系统，在该生态系统中，第三方还可以向云平台提供管理程序级别的服务，并增强基本管理程序的服务。要使用多个管理程序级别的服务，云用户可以运行多个管理程序虚拟机，它被设想为同时在多个共存的管理程序上运行的未经修改的虚拟机。这个项目有两个推动力。首先是开发系统软件以透明地运行多个管理程序VM，其中多个管理程序使用嵌套的虚拟化协作控制VM的内存、虚拟CPU和I/O设备。第二个重点是研究各种管理程序级别服务共存的机制，并演示上面列出的服务的多管理程序生态系统。通过支持第三方管理程序生态系统，多管理程序VM背后的技术可以显著提高云平台的功能和性能。研究与教育的结合包括课程模块和项目，以及高级主题研究生课程。更广泛的影响包括在研究中指导本科生和代表性不足的学生，向当地高中推广，以及技术转让。

Modern cloud computing platforms offer users an array of choices in operating systems, database systems, financial software, virtual network routers, and so forth, all of which can be easily customized and executed within Virtual Machines (VM). Unfortunately, this level of user choice has not extended to the underlying systems software, called the hypervisor, which enables the cloud infrastructure to run VMs. On one hand, cloud providers have an opportunity to differentiate their service by offering rich hypervisor-level services such as rootkit detection, live patching, intrusion detection, high availability, and VM introspection. On the other hand, it is difficult for a cloud provider to develop and maintain a single hypervisor that incorporates every feature that each cloud user wants. This research is to enable a software ecosystem in which third-parties can also contribute hypervisor-level services to the cloud platform and augment the services of a base hypervisor. To use multiple hypervisor-level services, a cloud user can run a multi-hypervisor virtual machine, which is envisioned as an unmodified VM that simultaneously runs atop multiple co-existing hypervisors. There are two thrusts of this project. The first is to develop the systems software to transparently run multi-hypervisor VMs, where multiple hypervisors co-operatively exert control over the memory, virtual CPUs, and I/O devices of a VM using nested virtualization. The second thrust is to investigate mechanisms for the co-existence of various hypervisor-level services and demonstrate a multi-hypervisor ecosystem of services such as those listed above. By enabling an ecosystem of third-party hypervisors, the technology behind multi-hypervisor VM can significantly improve the functionality and performance of the cloud platforms. Integration of research with education includes course modules and projects, and an advanced topics graduate course. Broader impacts include mentoring undergraduate and under-represented students in research, outreach to local high schools, and technology transfer.