Joined: 06 Jun 2008 Posts: 8187 Location: East Dubuque, Illinois, USA
If a DB2/COBOL prog is takin 5 hours then how the execution time can be reduced to say 40 mins.
How do you know this goal can be achieved, even?
First, you have to find out if the job is CPU-bound or I/O-bound. For CPU-bound jobs, find out what is taking all the CPU time and minimize it (which may reduce the run time but may not). For I/O-bound jobs, you can work with your site storage team to reduce channel and disk contention, but this again may or may not reduce run time.
Bottom line: there are no guaranteed, 100% effective all-the-time methods to reduce run time. If the run time has already been reduced to the minimum, then short of buying a faster machine with faster disk drives there may no way to reduce the run time.