Are concurrency issues possible when using the WCF Service Behavior attribute set to ConcurrencyMode.Multiple and InstanceContextMode.PerCall?

Question

We have a WCF service that makes a good deal of transactional NHibernate calls. Occasionally we were seeing SQL timeouts, even though the calls were updating different rows and

Answer 1

I believe the answer is the fact that there are multiple threads (on the client side) utilizing the same proxy instance, thus potentially allowing for multiple calls into the same instance. This post has a more detailed explanation.