Ask HN: How do you load test your application?

We're looking at ways to load test our AWS hosted SaaS product.

The application is behind load balancers and takes advantage of Elastic Beanstalk's auto scaling. It would be good to get an idea of how much, and what type of traffic we can handle before the application begins to scale up.

We are looking at using Goad (https://goad.io/).

Does anyone have any other recommendations or advice?