CSR: Small: Collaborative Research: Instruction Address Translation Revisited

应用程序的代码规模和访问的数据量都在持续增长。无论是在移动平台、桌面平台还是服务器平台上，应用程序都是以模块化的方式编写的，在很大程度上依赖于大量库提供的公共功能。现代操作系统通过跨应用程序共享库来利用这种通用性，以避免内存中指令的重复副本。然而，操作系统仍然为每个进程维护独立的内存管理（地址转换）数据，消耗的内存资源与同时执行的进程数量成正比。这个项目的目标是提高内存系统访问和管理共享代码库的效率。这些努力的成功将有助于世界快速发展的数字经济和社会的长期可持续性，减少计算浪费并提高响应能力。教育部分将包括通过提供新的课程模块来改善课堂教学，以及培训研究生有效共享的重要性。该项目涉及设计新颖的硬件和软件，以促进在多任务环境中对共享代码的有效访问，包括：1)新的操作系统内存管理机制和策略，以消除重复并最小化缓存和翻译外置缓冲区（TLB）占用，检查使用可变段和分层页表之间的权衡；2)在利用新兴的低延迟持久内存时，重新审视缓存翻译的必要性；3)除了设计新的硬件支持以提高效率外，在现代tlb中使用可用的保护支持来实现安全翻译共享。

Applications continue to grow both in the size of their code and in the amountof data they access. Whether on mobile, desktop, or server platforms,applications are written in a modular fashion, relying heavily on commonfunctionality provided by a large number of libraries. Modern operatingsystems leverage this commonality by sharing libraries across applications toavoid duplicate copies of instructions in memory. However, operating systemsstill maintain independent memory management (address translation) datafor each process, consuming memory resources proportional to the number ofsimultaneously executing processes. The goal of this project is to enhancethe efficiency of memory system access and management for shared codelibraries. The success of these efforts will contribute to the long-termsustainability of the world's fast evolving digital economy and society,reducing computational waste and improving responsiveness. The educationcomponent will include improving classroom instruction by contributing newcourse modules as well as training graduate students in the importance ofefficient sharing.This project involves designing novel hardware and software to promoteefficient access to shared code in a multi-tasking environment, including: 1)new operating system memory management mechanisms and policies to eliminateduplication and minimize cache and translation lookaside buffer (TLB)footprint, examining the tradeoffs between the use of variable segments andhierarchical page tables; 2) reexamining the need for caching translationswhen utilizing emerging low-latency persistent memory; and 3) using availableprotection support for safe translation sharing in modern TLBs in addition todesigning new hardware support to improve efficiency.