SHF: Small: Precise Concurrency Exceptions: Architecture Support, Semantics and System Implications

如何普及并行编程是计算研究协会对系统社区的重大研究挑战之一。能够充分利用多核系统的潜力将使我们重新获得可用性能的指数增长，并带来显著的节能效果。促进多线程程序的正确和高效执行将在IT行业产生革命性的影响，因为它解决了多处理器系统中可编程性问题的核心问题。随着无处不在的多核和新兴的并行程序的出现，IT行业现在正在处理更困难的可靠性问题。并发错误是很难理解的，通常是非确定性的，并且在它们发生的时候就会显现出来。此外，它们还对编程语言语义有重大影响。最近关于并发调试支持的工作取得了很好的进展，但通常集中在具有概率保证的错误检测的尽力而为技术上。这项研究对这个问题采取了一种直接的方法：通过在错误显现之前提交异常来使并发错误失败-停止。换句话说，系统检测到并发错误即将发生，并将在允许执行出现错误的代码之前引发异常。调查人员称这种机制为并发例外。并发异常将允许像被零除和分段错误一样方便地处理并发错误。

How to popularize parallel programming is one of the Computing Research Association's Grand Research Challenges for the systems community. Being able to leverage the full potential of multi-core systems would put us back into exponential growth of usable performance, as well as lead to significant power savings. Facilitating correct and efficient execution of multithreaded programs would have a transformative effect in the IT industry, as it attacks a problem at the heart of the programmability issues in multiprocessor systems. With ubiquitous multicores and emerging parallel programs, the IT industry is now dealing with far harder reliability problems. Concurrency errors are hard to understand, are typically non-deterministic and manifest themselves way past the point of their occurrence. Moreover, they have major implications for programming language semantics. Recent work on support for concurrency debugging has made good progress, but has often focused on best-effort techniques for bug detection with probabilistic guarantees. This research takes a direct approach to the problem: making concurrency errors fail-stop by delivering an exception before the error manifests itself. In other words, the system detects that a concurrency error is about to happen and will raise an exception before the code with an error is allowed to execute. The investigators call this mechanism concurrency exceptions. Concurrency exceptions will allow concurrency errors to be handled as conveniently as division by zero and segmentation fault.