Re:Rust for AWS Lambda, the Docker Way
by newfocogi on Tuesday November 26, 2024 @02:34PM
(#42249117)
One of the massive benefits for Rust on Lambda is (as the author mentions) "extremely low start-up time, CPU usage and memory footprint". It's not clear to me if deploying Rust to Lambda via a docker image actually negates some of those benefits.
[ Parent
| on HN ]
Using Lambda functions stored in ECR has no impact on performance from my experience. AWS Lambda uses Firecracker under the hood, which builds a VM from a container image. It's likely that non-ECR image based Lambdas are actually packaged as a container image before being launched into a Firecracker VM.
https://aws.amazon.com/blogs/aws/firecracker-lightweight-vir...
This has been my experience as well, there was little to no impact on execution time at least.
Good question! I ran some benchmarks before because I was also curious and besides some slightly larger standard deviation for cold starts execution time, there was so significant difference in performance when using docker.