NGS: A Computing Environment Based on Hardware Transactional Memory

摘要：Charles Leiserson，CNS-0305606并行性在程序中引入了更多不想要的不确定性的机会，使得它们很难调试，也不可能为其编写可靠的回归测试。因此，并行计算已经成为一种仅适用于愿意处理并发复杂性的软件开发人员的利基技术，因为性能就是他们的一切。1993年，Herlihy和Moss{58}提出将事务内存作为实施原子性的替代机制，因为它允许用户避免锁定的许多复杂性。使用事务性内存，程序可以作为单个原子操作读取和修改多个不同的内存位置，这与数据库事务中发生的情况非常相似。趋势是软件事务存储器(STM){98，57，56}，其开销阻碍了事务的使用。该项目认为，“事务无处不在”的方法可以极大地简化并行编程，而硬件支持可以使管理费用微不足道。为了验证项目假设，他们计划开发一个带有软件模拟器的“可扩展”HTM的硬件规范，一个类似C语言的语言框架，支持“隐式”事务的编译器，调试器和其他软件工程工具，语义和性能的理论基础，以及展示HTM计算环境优势的多线程应用程序。

Abstract:Charles Leiserson, CNS-0305606Parallelism introduces more opportunities for unwanted nondeterminism in programs, making them hard to debug and impossible to write reliable regression tests for. Consequently, parallel computing has emerged as a niche technology suited only for software developers who are willing to cope with the complexities of concurrency, because performance is everything for them.In 1993, Herlihy and Moss{58} proposed transactional memory as an alternative mechanism for enforcing atomicity, since it allows the user to avoid many of the complications of locking. With transactional memory, a program can read and modify multiple, disparate memory locations as a single atomic operation, much as occurs within a database transaction. The trend has been towards software transactional memory(STM) {98,57,56}, the overhead of which discourages the use of transactions. The project contends that the "transactions everywhere" approach can simplify parallel programming dramatically and that hardware support can make overheads negligible. To test the project hypothesis, they plan to develop a hardware specification of "scalable" HTM with a software simulator, a linguistic framework for C-like languages, complier support "implicit" transactions, debuggers and other software-engineering tools, theoretical foundations for semantics and performance, and multithreaded applications that demonstrate the advantages of an HTM computing environment.