Is there a way to tell how many "Concurrent Calls" are being made to a WCF service?

I've a WCF service that at the moment 11 clients ping in to every 3 minutes. They have all been running fine for a couple weeks. Last night, they all of a sudden stopped being able to ping in due to timing out. So I looked at my server web.config. Specifically:

<serviceThrottling maxConcurrentCalls ="50" maxConcurrentSessions="200"/>

which should have no problems working.

I changed both 开发者_StackOverflow社区values to 500, saved the file, and everything started working again. So it must have been some issue with how many connections where being made.

My question is: is there a way to view on the server app how many concurrent calls there are currently? Like some sort of monitoring system? This would help me to find why 50 possible calls was not enough for 11 clients.

Question 2: Does editing a service's web.config, then saving it, reset all the connections? Or was it just that I made the concurrent calls larger?

You might want to look at the WMI instrumentation available:

http://msdn.microsoft.com/en-us/library/ms735098.aspx

Windows Communication Foundation (WCF) includes a large set of performance counters to help you gauge your application's performance.