Defining structure size for CQS connections

Use the INITSIZE and SIZE parameters of the z/OS® CFRM policy to define the size of the CQS structures.

The size of the structures to which CQS connects is defined in the CFRM policy by defining the INITSIZE (initial size of the structure) and SIZE (maximum size of the structure) parameters. If enough free space does not exist for this INITSIZE value, the size of the structure becomes that of the available space in the coupling facility.

To determine what structure size to define in the CFRM policy, you can use the System z® Coupling Facility Structure Sizer Tool (CFSizer). CFSizer is a web-based application that calculates the structure size based on the input data you provide. CFSizer is available at System z Coupling Facility Structure Sizer Tool (CFSizer) web page.

You can use the z/OS structure alter process to change the structure size or to redistribute the objects within the structure after it has been defined. For information, see Using structure alter for CQS.