CSR-PSCE, SM: An Operating System for Multi-core Processors

该项目正在开发一个名为Corey的新操作系统，旨在帮助系统软件和应用程序在多核系统上实现高性能。 当前的多处理器操作系统内核通常提供抽象，其语义隐含地要求在处理器之间共享数据，并且使用受锁保护的共享数据结构来实现。 这种方法可能会导致内核成为数据和锁的竞争的瓶颈，即使对于不需要共享语义的应用程序也是如此。Corey基于应用程序应该控制所有共享的原则：所有内核数据结构应该是处理器核心的本地数据结构，除非应用程序另有指示。Corey公开了一组新的低级抽象（共享、地址树和内核），允许应用程序控制所有的内核间共享。Corey通过允许应用程序和内核子系统将内核专用于处理特定功能和数据来利用可能丰富的内核。 预期的结果是，应用程序可以定制它们对处理器和共享内存的使用，以实现最大的性能。这些想法正在通过实现Web服务和MapReduce处理等应用程序进行评估，并将实现的容易程度和性能与为更传统的操作系统（如Linux）构建的实现进行比较。Corey将作为开源软件发布，如果可能的话，特定的成功技术将被移植到Linux。 这些想法和软件将用于麻省理工学院的本科操作系统课程，让学生体验多核编程。在更高的层面上，这项工作旨在帮助缩小可用计算能力与软件驾驭能力之间的差距，这可能会帮助许多计算机用户。

This project is developing a new operating system, called Corey, intended to help systems software and applications achieve high performance on multicore systems. Current multiprocessor operating system kernels typically provide abstractions whose semantics implicitly require sharing data among processors, and which are implemented with shared data structures protected by locks. This approach may cause the kernel to be a bottleneck due to contention for data and locks, even for applications that do not require sharing semantics.Corey is based on the principle that applications should control all sharing: all kernel data structures should be local to a processor core unless directed otherwise by the application. Corey exposes a new set of low-level abstractions (shares, address trees, and kernel cores) that allow applications to control all inter-core sharing. Corey takes advantage of the likely abundance of cores by allowing applications and kernel sub-systems to dedicate cores to handling specific functions and data. The intended result is that applications can tailor their use of processors and shared memory to achieve maximum performance.These ideas are being evaluated by implementing applications such Web services and MapReduce processing, and comparing both ease of implementation and performance to implementations built for more traditional operating systems such as Linux. Corey will be released as open source, and specific successful techniques will be ported to Linux when possible. The ideas and software will be used in MIT's undergraduate operating systems course, to give students experience with multicore programming. At a higher level, the work is intended to help shrink the gap between available compute power and software's ability to harness it, potentially helping many users of computers.