Tuning CPU-Management Parameters

This section describes database server configuration parameters you can use to tune CPU use, especially virtual processors that run on CPUs.

This chapter does not provide information about the following basic CPU-management parameters, which should be set appropriately when you start the database server the first time:

• UNIX parameters that affect CPU use, such as semaphore parameters, parameters that set the maximum number of open file descriptors, and memory configuration parameters.

  Database server performance depends on correct settings of these parameters as described in IBM Informix: Administrator's Guide and in the Machine Notes for your platform. If you cannot control the UNIX parameters directly, discuss this information with your Information Services (IS) department.

• Processor-affinity parameters that bind specific CPUs to processes:
  • AFF_SPROC
  • AFF_NPROCS

For information, refer to your machine notes and the IBM Informix: Extended Parallel Server Administrator's Guide.