I am looking out for a strategy to utilize multithreading (probably asynchronous delegates) to do a synchronous operation. I am new to multithreading so i will outline my scenario first. This synchronous operation right now is done for one set of data (portfolio) based on the the parameters provided. The (psudeo-code) implementation is given below:

public DataSet DoTests(int fundId, DateTime portfolioDate)
{
    // Get test results for the portfolio
    // Call the database adapter method, which in turn is a stored procedure,
    // which in turns runs a series of "rule" stored procs and fills a local temp table and returns it back.
    DataSet resultsDataSet = GetTestResults(fundId, portfolioDate);

    try 
    {

        // Do some local processing on the results
        DoSomeProcessing(resultsDataSet);

        // Save the results in Test, TestResults and TestAllocations tables in a transaction.

        // Sets a global transaction which is provided to all the adapter methods called below
        // It is defined in the Base class
        StartTransaction("TestTransaction");    

        // Save Test and get a testId
        int testId = UpdateTest(resultsDataSet);    // Adapter method, uses the same transaction

        // Update testId in the other tables in the dataset
        UpdateTestId(resultsDataSet, testId);

        // Update TestResults
        UpdateTestResults(resultsDataSet);          // Adapter method, uses the same transaction

        // Update TestAllocations
        UpdateTestAllocations(resultsDataSet);      // Adapter method, uses the same transaction

        // It is defined in the base class
        CommitTransaction("TestTransaction");
    }
    catch
    {
        RollbackTransaction("TestTransaction");
    }
        return resultsDataSet;
}

Now the requirement is to do it for multiple set of data. One way would be to call the above DoTests() method in a loop and get the data. I would prefer doing it in parallel. But there are certain catches:

• StartTransaction() method creates a connection (and transaction) every time it is called.
• All the underlying database tables, procedures are the same for each call of DoTests(). (obviously).

Thus my question are:

• Will using multithreading anyway improve performance?
• What are the chances of deadlock especially when new TestId's are being created and the Tests, TestResults and TestAllocations are being saved? How can these deadlocked be handled?
• Is there any other more efficient way of doing the above operation apart from looping over the DoTests() method repeatedly?