3 Replies Latest reply on Sep 9, 2010 4:47 AM by 795890

    Oracle.DataAccess - Connection Pool Problem


      Oracle.DataAccess is having connection pool problem. The no. of TCP connections to Oracle database keep increasing untill the server's session run out of limit. My application created connections, use them, close them, and dispose them properly. When using previous Oracle.DataAccess, the no. of TCP connections do not increase.

      My database connection string has "Min Pool Size = 3 and Max Pool Size = 150".
      With version, TCP connection stays at 3.
      With, TCP connection keep increasing for every 5 minutes. I've tried to disable Self Tuning, but still can't prevent the connections from increasing.

      Later today, I downloaded Oracle.DataAccess (it comes with ODAC and test again, the problem is resolved... no more connection increases... but.... it is only for 32 bit Windows.

      Unfortunately, there is no Oracle.DataAccess for 64 bit Windows Server 2008.

      May I know how can i resolve this problem on 64bit Window installed with Oracle 11g R2 client, which comes with Oracle.DataAccess, which has serious problems...(according to this 11.2 ODP.NET causing test runner failures )

      Many thanks for your time and answers!

      Edited by: user1502907 on 04-Sep-2010 23:01
        • 1. Re: Oracle.DataAccess - Connection Pool Problem
          As a work around, we use 32 bit Oracle 11g Release 2 ODAC on Windows 2008 R2 64bit server. The application pool in IIS was then set to 'Enable 32-Bit Applications = true'.

          Once set, connections to database server is at a steady no. 3, which is the Min Pool Size value.

          Oh, by the way, the ODP.NET that comes with Oracle 11g r2 client does not produce any Windows Performance Counter. Only the 32 bit ODAC produce the Windows Performance Counter.

          I used TCPView.exe to monitor the no. of connections.

          I do hope that someone would answer for the 64bit ODAC on 11g r2.
          • 2. Re: Oracle.DataAccess - Connection Pool Problem
            Jenny -Oracle

            The only thing that jumps out within your problem description is that connections are being increased every 5 minutes. Are you sure its every 5 minutes and not 3 minutes which is the timing interval used by the Connection Pool facility to perform connection pool maintenance. If this occurs even when the application is idle then you could be running into the following known issue filed against and fixed in


            This is specific to using the option CommandBehavior.CloseConnection when calling execute reader. Are you using this option and then also closing the connection in code before the datareader object is closed, if so you may be hitting this bug. You can also generate an ODP trace at level 15 of the behavior and if you see negative pool counts, that is also a diagnostic that points to this bug.

            This is fixed in Patch 3 or later for x64. If you have support, I recommend you open a service request to verify if this is your issue and if a patch set may help you.

            Jenny B.
            • 3. Re: Oracle.DataAccess - Connection Pool Problem
              Thank you so much. You are right. It is every 3 min, not 5 min. I was estimating the interval when posting my question here.

              For the moment, we decided to use 32 bit mode.