Is scaling_config.maximum_concurrency of Event Source Mappings binding lambdas to sqs supported in Localstack?

Feature Requests
1

Whatever I set this config value to, localstack anyway starts new lambdas on any new message in a queue no matter how many are already running.

2

Hi @mif :wave:

The MaximumConcurrency ScalingConfig for SQS in Lambda Event Source Mapping is not yet supported. However, we are actively working on it. Stay tuned for more updates in the coming weeks :rocket:.

As a temporary workaround, you can use Reserved Concurrency on the Lambda function itself.

1 Like
3

Hi @mif

Quick update: Concurrency is still not supported in our new implementation, but a lot of other things improved :chart_with_upwards_trend: . We created a behavior coverage feature table to communicate it openly: Lambda | Docs
Feel free to create a GitHub issue if you are missing this feature.

Nevertheless, worth sharing: Check out our new Lambda event source mapping (ESM) implementation in LocalStack v4 offering better functional and non-functional support for ESM :rocket: .