Evaluating performance

Fill in the following worksheet to help you evaluate the performance of your program. If you answer yes to each question, you are probably improving the performance.

In thinking about the performance tradeoff, be sure you understand the function of each option as well as the performance advantages and disadvantages. You might prefer function over increased performance in many instances.

Table 1. Performance-tuning worksheet
Compiler option Consideration Yes?
ARCH Do you use the highest architecture level possible for all environments in which your programs will run? For example, if the lowest level architecture you have including your disaster recovery machines is z10, are you using ARCH(8)?  
AWO Do you use the AWO option when possible?  
BLOCK0 Do you use BLOCK0 for QSAM files?  
DATA When you use QSAM striped data sets, do you use the RENT and DATA(31) options? Is the program object AMODE 31? Are you running with ALL31(ON)?  
DYNAM Can you use NODYNAM? Consider the performance tradeoffs.  
FASTSRT When you use direct work files for the sort work files, did you use the FASTSRT option?  
Start of changeINLINEEnd of change Start of changeDo you use INLINE when possible?End of change Start of change End of change
Start of changeNUMCHECKEnd of change Start of changeDo you use NONUMCHECK for production runs?End of change Start of change End of change
NUMPROC Do you use NUMPROC(PFD) when possible?  
OPTIMIZE Do you use a non-zero OPTIMIZE level for production runs?  
Start of changePARMCHECKEnd of change Start of changeDo you use NOPARMCHECK for production runs?End of change Start of change End of change
SSRANGE Do you use NOSSRANGE for production runs?  
TEST Do you use NOTEST or TEST(NOEJPD) for production runs?  
TRUNC Do you use TRUNC(OPT) when possible?  
ZONEDATA Do you use ZONEDATA(PFD) when possible?  

related concepts  
Storage and its addressability

related references  
Performance-related compiler options