The Design, Productization, and Evaluation of a Serverless Workflow-Management System

Abstract

The need for accessible and cost-effective IT resources has led to thenear-universal adoption of cloud computing. Within cloud computing,serverless computing has emerged as a model that further abstracts awayoperational complexity of heterogeneous cloud resources. Central to this form ofcomputing is Function-as-a-Service (FaaS); a cloud model that enablesusers to express applications as functions, further decoupling the applicationlogic from the hardware and other operational concerns. Although FaaS has seenrapid adoption for simple use cases, there are several issues that impede itsuse for more complex use cases. A key issue is the lack of systems thatfacilitate the reuse of existing functions to create more complex, composedfunctions. Current approaches for serverless function composition are eitherproprietary, resource inefficient, unreliable, or do not scale. To address thisissue, we propose an approach to orchestrate composed functions using reliablyand efficiently with workflows. As a prototype, we design and implementFission Workflows: an open-source serverless workflow system which leverages thecharacteristics of serverless functions to improve the (re)usability,performance, and reliability of function compositions. We evaluate our prototypeusing both synthetic and real-world experiments, which show that the system iscomparable with or better than state-of-the-art workflow systems, while costingsignificantly less. Based on the experimental evaluation and the industryinterest in the Fission Workflows product, we believe that serverless workfloworchestration will enable the use of serverless applications for more complexuse cases.Computer Scienc