Can anyone speak to how NetSuite handles concurrent requests to a RESTlet? Ex: I have a restlet that receives a POST request and creates a few records in NetSuite based on that request. If 2 External Sources send a POST request at the same time... Do they both get processed? If so, does that happen concurrently? Does one get processed before the other? Does one get rejected?

They should process concurrently. I don't believe there's any queuing system for Restlet requests, even to the same Restlet. You won't be able to rely on requests processing in exactly the order they were received; subsequent requests may process faster than earlier ones. As long as subsequent requests are operating on different records, they shouldn't collide; if they operate on the same records, then you have a race condition, and you will likely run into

Record has been changed

errors.

Assuming they arent processing on the same records… If request 1 happens and then request 2 happens (1 second later), you’d expect both to process?

Yes

Thank you!

even 0ms later - NS supports concurrency on RESTlets up to an account specific limit.

Yes they will run concurrently up to your max concurrency allowed on the integration and/or account. It’s the same as the native REST and SOAP web services concurrency.

@Israel Gonzalez Is there a place I can see what my max concurrency allowed is?

Do you have NetSuite APM installed? If you don't definitely recommend going through it and installing it. If you their is already a concurrency monitor page