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Given the fundamental tradeoff between run-time and recovery performance, current distributed systems often build application-specific recovery strategies to minimize overheads. However, it is increasingly common for different applications to be composed into heterogeneous pipelines. Implementing multiple interoperable recovery techniques in the same system is rare and difficult. Thus, today's users must choose between: (1) building on a single system, and face a fixed choice of performance vs. recovery overheads, or (2) the challenging task of stitching together multiple systems that can offer application-specific tradeoffs. We present ExoFlow, a universal workflow system that enables a flexible choice of recovery vs. performance tradeoffs, even within the same application. The key insight behind our solution is to decouple execution from recovery and provide exactly-once semantics as a separate layer from execution. For generality, workflow tasks can return references that capture arbitrary inter-task communication. To enable the workflow system and therefore the end user to take control of recovery, we design task annotations that specify execution semantics such as nondeterminism. ExoFlow generalizes recovery for existing workflow applications ranging from ETL pipelines to stateful serverless workflows, while enabling further optimizations in task communication and recovery.
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Mixed Modality Workflows in TaskVine
Modern scientific workflows desire to mix several different comput- ing modalities: self-contained computational tasks, data-intensive transformations, and serverless function calls. To date, these modali- ties have required distinct system architectures with different sched- uling objectives and constraints. In this paper, we describe how TaskVine, a new workflow execution platform, combines these modalities into an execution platform with shared abstractions. We demonstrate results of the system executing a machine learning workflow with combined standalone tasks and serverless functions.
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- Award ID(s):
- 1931348
- PAR ID:
- 10567841
- Publisher / Repository:
- ACM
- Date Published:
- ISBN:
- 9798400701559
- Page Range / eLocation ID:
- 331 to 332
- Format(s):
- Medium: X
- Location:
- Orlando FL USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3588195.3595953
