CSR: CC: Large: A High-Performance Data Center Operating System

如今，许多流行的云数据中心应用程序花费大量时间运行操作系统代码。 示例包括实现Facebook、Google、Amazon和其他流行网站的后端服务。 这些应用程序花费大量时间移动、处理和存储数据。然而，在传统的操作系统中，操作系统内核作为在数据中心内提供应用程序、数据和网络安全性的手段来调解所有网络和存储访问。 因此，网络或存储请求从应用程序代码通过内核到设备硬件（然后再返回）的代码路径比所需的最小值长许多倍。这项工作通过更改操作系统内核、应用程序运行时库和设备硬件的角色，在不损害安全性的情况下简化了这些应用程序的性能。相反，内核的传统角色被一分为二。 应用程序可以直接访问虚拟化的I/O设备，允许大多数I/O操作完全跳过内核。 内核主要在控制平面中操作，根据操作系统安全策略建立和限制数据平面连接。 这项工作有可能大大提高应用程序和服务器的性能，以及数据中心的能耗和协议的灵活性。 地球仪上每天有数十亿人使用网络和存储密集型数据中心应用程序。 通过减少网络和存储这些应用程序的开销，可以减少支持现有服务所需的硬件，从而降低开发新服务的成本。

Today, many popular cloud data center applications spend a huge fraction of their time running operating system code. Examples include the backend services implementing Facebook, Google, Amazon, and other popular websites. These applications spend much of their time moving, processing, and storing data. In a traditional operating system, however, the operating system kernel mediates all network and storage access, as a means to provide application, data, and network security within the data center. Thus, the code path for a network or storage request to traverse from application code through the kernel to the device hardware (and back again) is many times longer than the minimum required.This work streamlines the performance of these applications without compromising security by changing the roles of the operating systems kernel, application runtime library, and device hardware. Instead, the traditional role of the kernel is split in two. Applications have direct access to virtualized I/O devices, allowing most I/O operations to skip the kernel entirely. The kernel operates primarily in the control plane, establishing and limiting data plane connections in accordance with the operating system security policy. The work has the potential for dramatic improvements in application and server performance, as well as data center energy consumption and protocol flexibility. Network and storage intensive data center applications are used by literally billions of people around the globe on a daily basis. By reducing the overhead of network and storage these applications, the hardware needed to support existing services can be reduced, making it cheaper for new services to be developed.