Published on feb 17, 2023
Amazon Web Services has recently announced the general availability of the Common Runtime (CRT) HTTP Client in the AWS SDK for Java 2.x. With this new asynchronous client, Lambda serverless workloads can now be launched more quickly and have a smaller memory footprint.
An asynchronous HTTP client built on top of the Java bindings of the Common Runtime libraries, AWSCrtAsyncHttpClient has been in preview for more than two years.
Additionally, AWS claims a reduction of up to 9% in P90 latency. In addition, the new asynchronous client offers better connection health management and DNS load balancing, according to the documentation.
The new HTTP client can be used by developers by adding the aws-crt-client dependency to their pom.xml file.
The default Netty client can be switched to the CRT client in a number of ways: specify it using the S3AsyncClient.builder() method, set the software.amazon.awssdk.http.async.service.impl property at startup of the JVM or directly in the code, with the client builder method being preferred.
AWS SDK for Java 2.0, released in 2018, provides features such as non-blocking IO, APIs for event streaming that implement the HTTP/2 protocol, and a pluggable HTTP implementation for further customization. By default, the SDK includes the netty-nio-client dependency. AWS recommends removing it from the application when using the new HTTP client to reduce the size.
As of version 2.20.0 of the Java 2 SDK, you can use the aws-crt-client.
