Question

While testing a new application, we came across an issue that sometimes a stored proc takes over 1 minute to execute and causes a time out. It was not 1 stored proc in particulary, it could be any.

Trying to reproduce the issue I’ve created a small (local) testapp that calls the same stored proc in different threads (code below).

Now it seems that the Oracle-sessions are still there. Inactive. And the CPU of the Oracle-server hits 100%.
I use the System.Data.OracleClient

I’m not sure if one is related to the other, but it slows down the time needed to get an answer from the database.

for (int index = 0; index < 1000; ++index)
{
    ThreadPool.QueueUserWorkItem(GetStreet, index);
    _runningThreads++;
    WriteThreadnumber(_runningThreads);
}

private void GetStreet(object nr)
{
    const string procName = "SPCK_ISU.GETPREMISESBYSTREET";
    DataTable dataTable = null;
    var connectionstring = ConfigurationManager.ConnectionStrings["CupolaDB"].ToString();
    try
    {
        using (var connection = new OracleConnection(connectionstring))
        {
            connection.Open();
            using (var command = new OracleCommand(procName, connection))
            {
                //Fill parameters
                using (var oracleDataAdapter = new OracleDataAdapter(command))
                {
                    //Fill datatable
                }
            }
        }
    }
    finally
    {
        if (dataTable != null)
            dataTable.Dispose();
    }
}

EDIT:
I just let the dba make a count of the open sessions and there are 105 sessions that stay open-inactive. After closing my application, the sessions are removed.

Answer 1

Problem is solved.

We hired an Oracle-expert to take a look at this and the problem was caused due to some underlying stored procedures that took a while to execute and consumed a lot of CPU.

After the necessary tuning, everything runs smoothly.