Processing Batch of 5000 Record in WCF Service Call

Depending on the average size of a single record, you may not be able to pass that much info to a service.

If it were me, I'd write a web method that accepted 1-to-n "records", so I can adjust the load in my code. Make the max possible records you can pass at any given time 100 (or whatever number you're comfortable with), and start hitting the method (in a test environment) to see what happens.

I'm not sure why you'd want to actually return the ID's that were generated when the records were inserted, but hey, I'v had stranger requests. Just return them in a XML string.