# 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.