Please Advice on Performance Tuning

[N J Neog]

Hi all,   We have got a Payroll Application develeoped in-house.   It takes 30-34 Minutes to Run this Batch Application. General feeling is - it should be able to process it within 10-15 Minutes may be less than that.   I am to look into this problem and give a solution to it.   Steps I had followed as   1. Import the payroll user to another Oracle User in the same database. 2. Removed unnecessary Index , Put parallelism into few    tables by Alter table tab1 Parallel(DEGREE 5) 3. Analyze the tables with compute statistics;   4. Run the payroll without checking any inefficient SQL or    wrong programming logic in the those Packages( It has only    two Package in it no other stand alone Procedure or  function).   Payroll under this new Oracle User runs in 22-24 Minutes, 6-9 Minutes less. So, I asked Payroll Person to remove those unnecessary Index, asked him to put parallelism into those tables which I had done. He runs the Payroll with no Improvement at all. I asked again to drop those table and recreate it with new storage parameter same as the one created at New User.  Still no visible Improvement.   At this stage every table in both user has same storage parameter,same index ,and also analyzed. The question is why in One User it runs in 22-24 Min and in another 30-34 Min ?   Now Please advice me what do I check or to do, so that the it time takes to run comes down to 22-24 Min, same as the new user.   Oracle 8.1.4 Optimize goal : choose Biggest table haiving record less than 60000 rows.   Thanks in Advance   Naba