aws_config load_from_env only once or before each DynamoDB request?

[Oliboy50]

Context

• I use aws-sdk-rust for a Rust web server which handles a relatively high traffic of HTTP requests (something like 1000 req/s).
• I use the Web Identity token mechanism to authenticate on DynamoDB services.

Question

In order to have the best possible performance using the Rust AWS SDK, is it fine to always call aws_config::load_from_env().await for each request to my Rust web server?

Because if I call aws_config::load_from_env().await only once during the boot of the Rust web server, at some point I will have to refresh the Web Identity token before it expires... and it's a pain... so I would love to know if aws-sdk-rust is efficient enough to support 1000 calls / second smoothly without having to wait several milliseconds for each call 🙏

[jdisanti]

aws_config::load_from_env() should be called once at the start of your application. The default credential chain automatically handles credentials caching and refresh. The SDK should definitely be efficient enough to handle the work load you're proposing, although you may encounter throttling from the services being called.

[Oliboy50]

The default credential chain automatically handles credentials caching and refresh

You mean that aws_config::load_from_env() keeps working in the background even after .awaiting the future?

Or is it the DynamoDB client which is in charge of refreshing the credentials when they expired, when we call something like dynamodb_client.get_item()?

[jdisanti]

The returned SdkConfig from load_from_env() holds a credentials cache in an Arc, and it gives the client a copy of that cache. When a request is made, the client asks that cache for credentials, and if those credentials have expired, the cache automatically reloads them.

[github-actions[bot]]

Hello! Reopening this discussion to make it searchable.