When you have determined which SMF parameters you want to change, place them in a SMFPRMxx parmlib member. The two alphameric characters, represented by xx, are appended to SMFPRM to identify your SMFPRMxx member. If you do not specify an SMFPRMxx member (with system parameters, such as SMF=01 for member SMFPRM01, or with an alternate member, such as IEASYSxx), the default member SMFPRM00 is used. You may place alternate values, or additional values, in one or more alternate SMFPRMxx members.
For information about coding the SMFPRMxx member, see z/OS MVS Initialization and Tuning Reference.