adam bien's blog

The AWS Lambda Cold Starts with Java and JavaScript 📎

Comparing the "warm" (invocation) and cold start performance of AWS Lambda functions written in JavaScript on node 14.0: 

exports.handler = async (event) => {

    return 'hello,js';
};

and Java on Amazon Corretto 11: 


public class Greetings{

    public String onEvent(Map<String, String> input) {
        return "hello, java";
    }
    
}

Both functions were deployed with the default configuration (128 MB RAM, default runtime).

Hint: the performance is similar

The Java AWS Lambda function was deployed with Java CDK with: https://github.com/AdamBien/aws-lambda-cdk-plain.