Author: Robert Sample
Posted: Sat Mar 18, 2017 6:36 pm (GMT 5.5)
First, unless you find a way to reduce the number of records being sorted, "optimizing SORT" is generally futile -- SORT has already been very optimized and there is usually little that can be done to reduce CPU usage.
Second, you need a run-time analysis program (such as STROBE) to be effective at reducing CPU usage. Programmers are generally poor at understanding what causes their programs to use CPU time, and hence having a tool will be vastly helpful.
Third, your best candidate for CPU reduction will be the SQL code. However, you may have to add disk space (for indexes, as one example) in order to reduce CPU usage.
Fourth, as Bill suggested -- talk to your production support group; they most likely know the best candidates to look at for CPU reduction!
Fifth, your post title "MIPS/CPU consumption reduction in Batch" is completely wrong. MIPS is a measurement that should NEVER be applied to anything less than the entire machine. MIPS can be reduced by removing the current machine and replacing it with a slower machine -- MIPS cannot otherwise be reduced. Yes, it is common to use MIPS and CPU interchangeably -- but they are not the same and should NEVER be swapped!
_________________
TANSTAAFL
The first rule of code reuse is that the code needs to be worth re-using.
"We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil." -- Donald Knuth
Posted: Sat Mar 18, 2017 6:36 pm (GMT 5.5)
First, unless you find a way to reduce the number of records being sorted, "optimizing SORT" is generally futile -- SORT has already been very optimized and there is usually little that can be done to reduce CPU usage.
Second, you need a run-time analysis program (such as STROBE) to be effective at reducing CPU usage. Programmers are generally poor at understanding what causes their programs to use CPU time, and hence having a tool will be vastly helpful.
Third, your best candidate for CPU reduction will be the SQL code. However, you may have to add disk space (for indexes, as one example) in order to reduce CPU usage.
Fourth, as Bill suggested -- talk to your production support group; they most likely know the best candidates to look at for CPU reduction!
Fifth, your post title "MIPS/CPU consumption reduction in Batch" is completely wrong. MIPS is a measurement that should NEVER be applied to anything less than the entire machine. MIPS can be reduced by removing the current machine and replacing it with a slower machine -- MIPS cannot otherwise be reduced. Yes, it is common to use MIPS and CPU interchangeably -- but they are not the same and should NEVER be swapped!
_________________
TANSTAAFL
The first rule of code reuse is that the code needs to be worth re-using.
"We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil." -- Donald Knuth