CRII: SHF: SimDB: An Automated Framework to Debug System-level Concurrency Faults

现代计算机系统利用多个CPU，连接到大量外围设备，并通过各种传感器和执行器感知它们的周围环境。由于各种形式的并发故障，这些系统的日益复杂可能会导致在其上运行的软件遭受部署故障。当部署的系统出现软件故障时，开发人员需要对系统进行调试，及时找出故障原因。不幸的是，调试大型复杂并发软件系统很困难。这是因为并发故障会间歇性地发生吗？因此很难再现，除非存在可能导致这种故障发生的特定交错。例如，故障可能涉及各种软件组件和系统事件的参与；再现这些可能需要重新创建许多因素或特定系统环境设置(例如，硬件、网络)的组合。该项目的目标是提供一个自动化框架，使工程师能够有效地调试已部署系统中的系统级并发故障。为了实现这一目标，该项目将研究和开发先进的静态和动态分析技术。具体地说，它将(I)开发可以识别潜在故障诱导程序路径的轻量级静态分析技术；(Ii)通过使用虚拟化来开发动态分析技术，以有效地再现由于不确定和异类系统事件而在部署的系统中发生的故障；(Iii)实现自动化调试框架，该框架提供丰富的用户界面以促进内部调试过程。该项目的结果将是一个可伸缩的、透明的框架，并且能够处理广泛类别的并发错误。该框架的使用过程基本上是自动化的，因此几乎不需要人工干预。因此，该框架有望帮助开发人员了解和纠正已部署系统中的故障，并使所有依赖此类系统的人受益。

Modern computer systems utilize multiple CPUs, connect to a large array of peripheral devices, and sense their surroundings through various sensors and actuators. The increasing complexity of these systems can cause software that runs on them to suffer from deployment failures due to various forms of concurrency faults. When a software failure occurs in the deployed system, developers need to debug the system and find the cause of the failure in a timely manner. Unfortunately, debugging large complex concurrent software systems is difficult. This is because concurrency faults occur ?intermittently? and are thus difficult to reproduce, unless there is a specific interleaving that can cause such faults to occur. For example, a failure may involve participation of various software components and system events; reproducing these may require recreating a combination of many factors or specific system environment settings (e.g., hardware,network). The goal of this project is to provide an automated framework that allows engineers to effectively debug system-level concurrency faults in deployed systems. To achieve this goal, the project will investigate and develop advanced static and dynamic analysis techniques. Specifically, it will (i) develop light-weight static analysis techniques that can identify potential failure-inducing program paths; (ii) develop dynamic analysis techniques by using virtualization to effectively reproduce failures that occur in the deployed systems due to nondeterministic and heterogeneous system events; (iii) implement an automated debugging framework that provides rich user interfaces to facilitate in-house debugging processes. The outcome of this project will be a framework that is scalable, transparent, and capable of dealing with broad classes of concurrency faults. The process by which the framework is employed is mostly automated so it requires little human intervention. As such, the framework is expected to help developers understand and correct failures in deployed systems, with benefits to all who depend on such systems.