Serverless Computing Revisited: Evolution, State-of-the-Art, and Performance Challenges

Market analysts are agreed that serverless computing has strong market potential, with projected compound annual growth rates varying between 21% and 28% through 2028 and a projected market value of 36.8 billion by that time. Although serverless computing has gained significant attention in industry and academia over the past years, there is still no consensus about its unique distinguishing characteristics and precise understanding of how these characteristics differ from classical cloud computing. For example, there is no wide agreement on whether serverless is solely a set of requirements from the cloud user's perspective or it should also mandate specific implementation choices on the provider side, such as implementing an autoscaling mechanism to achieve elasticity. Similarly, there is no agreement on whether serverless is just the operational part, or it should also include specific programming models, interfaces, or calling protocols. In this talk, we seek to dispel this confusion by evaluating the essential conceptual characteristics of serverless computing as a paradigm, while putting the various terms around it into perspective. We examine how the term serverless computing, and related terms, are used today. We explain the historical evolution leading to serverless computing, starting with mainframe virtualization in the 1960 through to Grid and cloud computing all the way up to today. We review existing cloud computing service models, including IaaS, PaaS, SaaS, CaaS, FaaS, and BaaS, discussing how they relate to the serverless paradigm. In the second part of talk, we focus on performance challenges in serverless computing both from the user's perspective (finding the optimal size of serverless functions) as well as from the provider's perspective (ensuring predictable and fast container start times coupled with fine-granular and accurate elastic scaling mechanisms).