At the moment in the constructor of QueueProcessingFargateService scaling steps can be defined, but cooldown parameter from autoscaling cannot:

this.service = new ecsPatterns.QueueProcessingFargateService(this, 'Service', {
      scalingSteps: [{...}, {...}],
      ....
    });

Proposed Solution

As far as I can see, the parameter should be provided here: https://github.com/aws/aws-cdk/blob/master/packages/@aws-cdk/aws-ecs-patterns/lib/base/queue-processing-service-base.ts#L270 in a similar fashion as scalingSteps.

Other

• I see that the behavior can be modified by extending QueueProcessingFargateService and overriding configureAutoscalingForService, but I believe that if scalingSteps is defined in the config, cooldown should be defined as well.
• While reading the code of the component QueueProcessingServiceBase, I found out that it has CpuScaling defined which cannot be affected anyhow by configuration, I believe it also should be modifiable. For my use case, scaling based on the queue size is enough.

This is a 🚀 Feature Request