Tuning your program

When a program is comprehensible, you can assess its performance. A tangled control flow makes a program difficult to understand and maintain, and inhibits the optimization of its code.

To improve the performance of your program, examine at least these aspects:

  • Underlying algorithms: For best performance, using sound algorithms is essential. For example:
    • A sophisticated algorithm for sorting a million items might be hundreds of thousands of times faster than a simple algorithm.
    • If the program frequently accesses data, reduce the number of steps to access the data.
  • Data structures: Using data structures that are appropriate for the algorithms is essential.

You can write programs that result in better generated code sequences and use system services more efficiently. These additional aspects can affect performance:

  • Coding techniques: Use a programming style that enables the optimizer to choose efficient data types and handle tables efficiently.
  • Optimization: You can optimize code by using the OPTIMIZE compiler option.
  • Compiler options and USE FOR DEBUGGING ON ALL PROCEDURES: Some compiler options and language affect program efficiency.
  • Runtime environment: Consider your choice of runtime options.
  • CICS®: To improve transaction response time, convert instances of EXEC CICS LINK statements to CALL statements.

    For information about improving performance of dynamic calls under CICS, see the Related tasks.

Related concepts