Lukewarm serverless functions

Abstract

Serverless computing has emerged as a widely-used paradigm for running services in the cloud. In serverless, developers organize their applications as a set of functions, which are invoked on-demand in response to events, such as an HTTP request. To avoid long start-up delays of launching a new function instance, cloud providers tend to keep recently-triggered instances idle (or warm) for some time after the most recent invocation in anticipation of future invocations. Thus, at any given moment on a server, there may be thousands of warm instances of various functions whose executions are interleaved in time based on incoming invocations.