CSR: Small: RUI: A Fast Backing Store System on top of Network RAM, Flash, and other Cluster-wide Storage

设计有效支持数据密集型计算的集群系统变得越来越重要。并行科学和多媒体应用程序经常执行大量的I/O，或者是由于交换而间接执行，或者是由于临时文件访问而直接执行。 随着磁盘与RAM、互连网络和闪存等其他硬件之间的速度差距不断扩大，访问磁盘的成本将日益成为系统性能的瓶颈。 本课题的目标是设计和实现一个适用于集群和局域网的快速备份存储系统。 我们的系统在多个异构群集范围的物理存储之上提供了一个单一的设备接口，特别是针对快速随机存取存储，如网络RAM和闪存。 我们的工作将使操作系统不再需要在其分页和文件系统中为底层物理存储设备的每个组合提供多个特定于设备的策略。 随着新技术的发展，我们系统的底层部分将把它们合并到它的异构物理存储集合中，但是操作系统将继续使用我们系统的同一个高层接口，即单个快速随机访问设备的接口。提供独立于底层物理存储的单一设备接口;创建能够适应资源利用率和容量变化的存储系统;以及开发和检查底层设备之间的数据放置和数据迁移策略。

It is increasingly important to design cluster systems that efficiently support data-intensive computing. Parallel scientific and multimedia applications often perform large amounts of I/O either indirectly, due to swapping, or directly, due to temporary file accesses. As the disparity between the speeds of magnetic disk and other hardware such as RAM, interconnection networks, and flash continues to grow, the cost of accessing disk will increasingly become the bottleneck to system performance. The objective of our project is to design and implement a fast backing storage system for clusters and local area networks. Our system provides a single device interface on top of multiple heterogeneous cluster-wide physical storage, particularly targeting fast random-access storage such as Network RAM and flash. Our work will free the OS from requiring multiple device-specific policies in its paging and file systems for every combination of underlying physical storage devices. As new technologies are developed, the low-level part of our system will incorporate them into its set of heterogeneous physical storage, but the OS will continue to use the same high-level interface of our system, that of a single, fast, random-access device.The main goals of our work are: to take advantage of all types of fast storage in a cluster; to provide a single device interface that is independent of the underlying physical storage; to create a storage system that can adapt to changes in resource utilization and capacity; and to develop and examine policies for data placement and data migration between underlying devices.