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Workflow management systems are widely used to express and execute highly parallel applications. For dataintensive workflows, storage can be the constraining resource: the number of tasks running at once must be artificially limited to not overflow the space available in the filesystem. It is all too easy for a user to dispatch a workflow which consumes all available storage and disrupts all system users. To address these issues, we present a three-tiered approach to workflow storage management: (1) A static analysis algorithm which analyzes the storage needs of a workflow before execution, giving a realistic prediction of success or failure. (2) An online storage management algorithm which accounts for the storage needed by future tasks to avoid deadlock at runtime. (3) A task containment system which limits storage consumption of individual tasks, enabling the strong guarantees of the static analysis and dynamic management algorithms. We demonstrate the application of these techniques on three complex workflows. 

Publishing scientific results without the detailed execution environments describing how the results were collected makes it difficult or even impossible for the reader to reproduce the work. However, the configurations of the execution environ- ments are too complex to be described easily by authors. To solve this problem, we propose a framework facilitating the conduct of reproducible research by tracking, creating, and preserving the comprehensive execution environments with Umbrella. The framework includes a lightweight, persistent and deployable execution environment specification, an execution engine which creates the specified execution environments, and an archiver which archives an execution environment into persistent storage services like Amazon S3 and Open Science Framework (OSF). The execution engine utilizes sandbox techniques like virtual machines (VMs), Linux containers and user-space tracers, to cre- ate an execution environment, and allows common dependencies like base OS images to be shared by sandboxes for different applications. We evaluate our framework by utilizing it to reproduce three scientific applications from epidemiology, scene rendering, and high energy physics. We evaluate the time and space overhead of reproducing these applications, and the effectiveness of the chosen archive unit and mounting mechanism for allowing different applications to share dependencies. Our results show that these applications can be reproduced using different sandbox techniques successfully and efficiently, even through the overhead and performance slightly vary.