CSR: Small: Making Software Transactional Memory More than a Research Toy

现在计算机技术似乎已经达到了Dennard扩展（增加时钟速率）的极限，软件必须变得更加并行，以便与提供更多而不是更快内核的硬件一起扩展。 然而，编写正确的、可伸缩的共享内存并发程序是出了名的困难。transmittance存储器（TM）在可编程性、可靠性和可缩放性方面提供了优于传统共享存储器系统的潜在改进。 然而，它并没有实现其最初的承诺，主要是因为没有人展示如何使其实用。硬件制造商不愿意将硬件TM（HTM）构建到已经复杂的高速缓存和存储器子系统中，并且软件TM（STM）遭受性能差和语义弱的问题。该项目旨在通过调查新的研究方向，使STM真正实用，通过实现高性能与强语义，大大提高了艺术水平。该项目解决了STM在现有工作中的关键成本-检测和处理冲突访问-使用一种新的机制，避免在非冲突访问同步。广泛提供实用STM支持的直接有益影响包括生产更可靠和可扩展的软件系统的能力，导致安全和任务关键型系统软件的进步。STM的广泛使用可以帮助刺激对混合硬件-软件TM的硬件支持的商业开发，这需要实际的STM支持。研究人员与工业研究人员的接触提供了加强传播的途径。 公开发布的STM实现本项目提供了进一步的研究和开发的基础。 一些教育和推广活动，包括课程项目，增强核心课程材料，互动演示的夏桥计划针对少数民族本科工程专业，并为未来的少数民族研究生招聘活动，旨在培养一个多元化的程序员和研究人员在开发未来的可靠，可扩展的软件系统。

Now that computer technology appears to have reached the limit of Dennard scaling (increasing clock rates), software must become more parallel, to scale with hardware that provides more instead of faster cores. However, writing correct, scalable shared-memory concurrent programs is notoriously difficult. Transactional memory (TM) offers potential improvements over conventional shared-memory systems in programmability, reliability, and scalability. However, it has not lived up to its initial promise, primarily because no one has shown how to make it practical. Hardware manufacturers are reluctant to build hardware TM (HTM) into already-complex cache and memory subsystems, and software TM (STM) suffers from poor performance and weak semantics. This project seeks to advance the state of the art dramatically by investigating new research directions for making STM truly practical, by achieving high performance with strong semantics. The project tackles STM's key cost in existing work -- detecting and handling conflicting accesses -- using a novel mechanism that avoids synchronization at non-conflicting accesses.Direct beneficial impacts of making widely available practical STM support include the ability to produce more reliable and scalable software systems, leading to advances in software for safety- and mission-critical systems. Widespread use of STM can help spur commercial development of hardware support for hybrid hardware-software TM, which requires practical STM support. The investigator's engagement with industrial researchers provides an avenue to enhance dissemination. Public distribution of STM implementations produced by this project provides a basis for further research and development. Several educational and outreach activities, including course projects, enhanced core course material, interactive presentations for a summer bridge program targeting minority undergraduate engineering majors, and recruiting events for prospective minority graduate students, aim to train a diverse group of programmers and researchers in developing future reliable, scalable software systems.