Published on Dec 05, 2022

The recent AWS re:Invent event announced an update to its FaaS offering AWS Lambda that reduces the cold start time for Java functions.

The Lambda functions on AWS are executed within a secure and isolated execution environment, and each environment has three main phases: Init, Invoke, and Shutdown. Init bootstraps the runtime for the function and runs its static code.

According to the company, the first phase of Init for some languages, such as Java, runtimes used in combination with frameworks such as Spring Boot, Quarkus, or Micronaut, can sometimes take up to ten seconds (including dependency injection, compilation of the function code, and scanning of classpath components). Additionally, the static code might download some machine learning models, precompute some reference data, or establish network connections to other AWS services.

A new version of a Lambda SnapStart function will trigger an optimisation process when Lambda SnapStart is enabled.

It is important to note that cached snapshots are deleted after 14 days of inactivity. Additionally, AJ Stuyvenberg, a lead software engineer at Datadog,

Lambda SnapStart is ideal for synchronous APIs, interactive microservices, and data processing applications.

Using the AWS Lambda API, AWS Management Console, AWS Command Line Interface (AWS CLI), AWS Cloud Formation, AWS Serverless Application Model (AWS SAM), AWS SDK, and AWS Cloud Development Kit (AWS CDK), developers can activate Lambda SnapStart for Java-based Lambda functions running on Amazon Corretto 11.

Lambda SnapStart is currently available in the US East (Ohio, North Virginia), US West (Oregon), Asia Pacific (Singapore, Sydney, Tokyo), and Europe (Frankfurt, Ireland, Stockholm).