sql server - Using Performance Monitor to monitor pooled connections -

i'm investigating error mvc3 application failing under load:

"the timeout period elapsed prior obtaining connection pool. may have occurred because pooled connections in use , max pool size reached."

the application using repository pattern , entity framework, , hunch it's not closing off connections properly. want able monitor number of pooled connections on sql server. searching around leads me believe can use these counters in perfmon:

• .net clr data
• .net data provider sqlserver

however both of them show , being disabled / grayed out.

i running perfmon directly on server, , both iss , sql server running on server. ideas why these counters not available?

i've tried using sql profiler monitor pooled connections, eventsubclass column isn't available auditlogin.

you can run sql query windows count , details of current connections , session running on sql server.

select * sys.dm_exec_sessions es   inner join sys.dm_exec_connections ec   on es.session_id = ec.session_id 

i've had trouble pooled connections. they're hard control. explicitly closing them never seemed work since they're under control of .net. biggest reason we've run out of connections uncommitted transactions. if transaction left uncommitted or rolled reason, connection, instead of being re-used, get's stuck in limbo, forcing .net open yet connection continue processing.