Issue with calling restful services via HTTP in an Orchestration

Question

The company I work for is using RESTful services for our I/O. We are processing EDI files using Biztalk, and are calling the REST services via HTTP from a c# code called within the orchestration. At lower volumes, the service performs fine, but at higher
transaction volumes, the HTTP calls never return. Is there a resource that needs to be tuned somewhere on the biztalk node to allow higher volumes of HTTP calls? Its not the REST service side - it has no problems handling loads generated by non biztalk nodes.
For further clarification, the EDI message is a multi batched, so there are many simultaneous orchestrations running at once.  I have started to look at ways to throttle how many instances can run at once, but I still suspect some resource in the HTTP
sequence that we dont have enough of.
Ideas?

Answer 1

I think you were not  enough free threads in the ThreadPool to complete the operation.
So you can work out with Max connection setting in your BTSNTSvc file first
<system.net>
<connectionManagement>
<add address="http://name.of.server.here" maxconnection="1oo" />
</connectionManagement>
</system.net>
and try increasing number of threads allocated to the specific send Host instance and your Orchestration instance  ,you can try twinkling Response timeout in minutes as well  on host instance
Thanks
Abhishek