Initiate alter processing using the SETXCF START,ALTER command. Altering is a nondisruptive method for changing the size of the list structure. Alter processing can increase the size of the structure up to the maximum size specified in the CFRM policy. The SETXCF START,ALTER command can also decrease the size of a structure to the specified MINSIZE or default to the value specified in the CFRM policy.