Collaborative Research: SI2-SSE: WRENCH: A Simulation Workbench for Scientific Worflow Users, Developers, and Researchers

许多科学突破只能通过有效地对大量数据进行复杂处理来实现。 在气候建模、海洋学、粒子物理学、地震学或计算生物学等对我们社会至关重要的领域（事实上，在今天的物理学、化学和生物学的大多数领域），科学家们现在通常定义“科学工作流程”。这些工作流是对科学过程的复杂描述，作为数据和对这些数据的相互依赖的计算。在执行时，通常需要大量的计算、存储和网络硬件，这些工作流可以产生突破性的结果。最近一个著名的例子是LIGO项目的工作流程，该工作流程用于确认首次探测到来自碰撞黑洞的引力波。科学工作流程是当今科学的支柱。因此，它们的有效执行（在速度、可靠性和成本方面）至关重要。该项目旨在提供一个名为WRENCH（工作流模拟器）的软件框架，该框架将使在一台计算机上快速准确地模拟大规模假设场景成为可能，从而避免了昂贵且耗时的试错实验。WRENCH可能使科学家在执行工作流程时做出快速和明智的选择，软件开发人员可以实现更高效的软件基础设施来支持工作流程，研究人员可以开发嵌入这些软件基础设施的新型高效算法。 此外，WRENCH还可以将科学工作流程内容纳入本科和研究生计算机科学课程。这是因为学生可以使用一台计算机和WRENCH软件堆栈获得有意义的知识，即使在无法访问高端计算基础设施的机构，例如许多非博士生，也可以进行这种学习。资助机构和少数群体服务机构。因此，这项工作将有助于生产计算机科学毕业生更好地装备在科学的进步中发挥积极作用。 由于其对科学工作流程的使用、开发、研究和教育的潜在变革性影响，该项目有望推动几乎所有领域的科学进步，最终为我们的社会带来广泛而众多的好处。科学工作流程已成为开展大规模科学研究的主流。 因此，许多工作流应用程序和工作流管理系统（WMS）已被开发为网络基础设施的一部分，以允许科学家在一系列分布式平台上无缝地执行他们的应用程序。 尽管有许多成功案例，但鉴于工作流本身的复杂性和底层执行平台的复杂性，构建大规模工作流并有效地编排其执行（在性能，可靠性和成本方面）仍然是一项挑战。 一个基本的必要的下一步是建立一个坚实的“实验科学”的方法，为未来的工作流技术的发展。这种方法对于需要设计工作流程和选择执行平台的科学家，需要比较替代设计和实施选项的WMS开发人员以及需要开发新的决策算法以作为WMS的一部分实施的研究人员都很有用。 这项工作的主要目标是提供基础软件，工作流仿真工具（WRENCH），在此基础上开发上述实验科学方法。 利用分布式应用程序和平台仿真技术的最新进展，WRENCH可以（i）快速原型化工作流，WMS实现和决策算法;以及（ii）针对任意的，通常是假设的实验场景，可扩展和准确地评估/比较替代选项。 该项目将定义一个通用的和基础的软件架构，这是由当前最先进的WMS设计和规划的未来设计通知。 在这个架构中的组件的实现一起形成了一个通用的“科学仪器”，可以被工作流用户，开发人员和研究人员使用。 这个科学仪器将被实例化为几个真实世界的WMS，并用于一系列真实世界的工作流应用程序。在一个特定的案例研究中，它将与流行的WMS（飞马座），重新审视已公布的结果和调度算法在该地区的工作流程规划优化。我们的目标是展示使用实验科学方法进行WMS研究的好处。 该项目的另一个影响是，它使得有可能在本科和研究生计算机科学课程中普遍包括科学工作流内容，即使是没有任何计算基础设施的学生，通过定义只需要一台计算机和WRENCH软件栈的有意义的教学活动。这种教育影响将在我们机构的本科和研究生课程的课堂上得到证明。

Many scientific breakthroughs can only be achieved by performing complex processing of vast amounts of data efficiently. In domains as crucial to our society as climate modeling, oceanography, particle physics, seismology, or computational biology (and in fact in most fields of physics, chemistry, and biology today), scientists nowadays routinely define "scientific workflows". These workflows are complex descriptions of scientific processes as data and inter-dependent computations on these data. When executed, typically with great expenses of computing, storage, and networking hardware, these workflows can produce groundbreaking results. A famous and recent example is the workflow that was used as part of the LIGO project to confirm the first detection of gravitational waves from colliding black holes. Scientific workflows are mainstays in today's science. Their efficient execution (in terms of speed, reliability, and cost) is thus crucial. This project seeks to provide a software framework, called WRENCH (Workflow Simulation Workbench), that will make it possible to simulate large-scale hypothetical scenarios quickly and accurately on a single computer, obviating the need for expensive and time-consuming trial and error experiments. WRENCH potentially enables scientists to make quick and informed choices when executing their workflows, software developers to implement more efficient software infrastructures to support workflows, and researchers to develop novel efficient algorithms to be embedded within these software infrastructures. In addition, WRENCH makes it possible to bring scientific workflow content into undergraduate and graduate computer science curricula. This is because meaningful knowledge can be gained by students using a single computer and the WRENCH software stack, making such learning possible even at institutions without access to high-end computing infrastructures, such as many non-Ph.D.-granting and minority-serving institutions. As a result, this work will contribute to producing computer science graduates better equipped to take an active role in the advancing of science. Due to its potentially transformative impact on scientific workflow usage, development, research, and education, this project promises to promote the progress of science across virtually all its fields, ultimately resulting in broad and numerous benefits to our society.Scientific workflows have become mainstream for conducting large-scale scientific research. As a result, many workflow applications and Workflow Management Systems (WMSs) have been developed as part of the cyberinfrastructure to allow scientists to execute their applications seamlessly on a range of distributed platforms. In spite of many success stories, building large-scale workflows and orchestrating their executions efficiently (in terms of performance, reliability, and cost) remains a challenge given the complexity of the workflows themselves and the complexity of the underlying execution platforms. A fundamental necessary next step is the establishment of a solid "experimental science" approach for future workflow technology development. Such an approach is useful for scientists who need to design workflows and pick execution platforms, for WMS developers who need to compare alternate design and implementation options, and for researchers who need to develop novel decision-making algorithms to be implemented as part of WMSs. The broad objective of this work is to provide foundational software, the Workflow Simulation Workbench (WRENCH), upon which to develop the above experimental science approach. Capitalizing on recent advances in distributed application and platform simulation technology, WRENCH makes it possible to (i) quickly prototype workflow, WMS implementations, and decision-making algorithms; and (ii) evaluate/compare alternative options scalably and accurately for arbitrary, and often hypothetical, experimental scenarios. This project will define a generic and foundational software architecture, that is informed by current state-of-the-art WMS designs and planned future designs. The implementation of the components in this architecture when taken together form a generic "scientific instrument" that can be used by workflow users, developers, and researchers. This scientific instrument will be instantiated for several real-world WMSs and used for a range of real-world workflow applications. In a particular case-study, it will be used with a popular WMS (Pegasus) to revisit published results and scheduling algorithms in the area of workflow planning optimizations. The objective is to demonstrate the benefit of using an experimental science approach for WMS research. Another impact of this project is that it makes it possible to include scientific workflow content pervasively in undergraduate and graduate computer science curricula, even for students without any access to computing infrastructure, by defining meaningful pedagogic activities that only require a computer and the WRENCH software stack. This educational impact will be demonstrated in the classroom in both undergraduate and graduate courses at our institutions.