I am using InvokeHttp processor with GET to send request to a remote Rest API to get http response. The throughtput is about 60 requests per minute and set concurrent task as 1 and run schedule as 3 seconds. The total requests to send will be aroud 5 thousand so expect within two hours. THe response body is not huge but everage is about 2K. The response from Rest API worked fine for a hour and then I saw upstream queue of this processor reached number of a few hundreds and then I saw no response from the Rest API and InvokeHttp processor seems freezen. Nothing happening at all. No timeout, no error, nothing continue to processing.
I take the connection token and request URL and run them against the rest API with Postman. The response came back from The Rest API and everyting look fine on that service. Contact the API provider and they ask to use Postman to check as I did already. Then I was told their service has no problem. Any thought what can cause something like I saw and recommendation to resolve it? Attach screen shot for this processor setting. 
