Switched from inproc to SQL Server gives me SQL timeouts (no connection max pool size, typed datasets)

Question

Hello everybody.

Here is my situation:

I have a web and database server (SQL Server 2005) in a LAN.

The webserver(iis6) has several application pools and sites run fine with asp.net session inproc. both servers run win 2k3

Now I switched from inproc to SQL Server and I get a lot of SQL timeout expired messages. But only from one web application that moved the sessions to SQL Server. All other websites are not affected. The timeouts occur on regular database queries which run fine when using inproc.

How do I troubleshoot this?

Thanks in advance!

best regards,

JP

edit: as requested my web.config of the web app which uses the SQL Server:

<sessionState 
       mode="SQLServer" 
       timeout="60" sqlConnectionString="Data Source=192.168.1.80;Persist Security Info=True;User ID=aspstate;Password=state"
       />

I also forgot to mention that the problem website with SQL Server shares an application pool with one web app which runs inproc. I just splitted the two web apps to their own app pools. But I don't think that that will resolve the timeouts. The strange thing is that all other websites stay running fine

edit 2: i have received this message today when i tried again to switch from inproc to sqlserver. as data access i use a lot of typed datasets (*.xsd) my web app is an e-commerce site which has about 2k unique visitors a day here is the message:

Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.

Answer 1

This sounds like your one specific application is leaking connections and filling up the connection pool for sql server resulting in the timeouts. Tracing these issues can be immensely frustrating, take a look at a profiler application and tools like procexp.