Call CSRIRP to define a reference pattern for a large data area, such as an array, that you are about to reference. Through CSRIRP, you identify the data area and describe the reference pattern. Additionally, you tell the system how many bytes of data you want it to bring into central storage on a page fault (that is, each time the program references data that is not in central storage). This action might significantly improve the performance of the program.

Reference units and gaps must each be uniform in size and appear throughout the data area at repeating intervals.

Another parameter, units, allows you to specify how many reference units you want the system to bring into central storage each time the program references data that is not in central storage.

When you end the reference pattern in that data area, call the CSRRRP service.

Code the CALL following the syntax of the high-level language you are using and specifying all parameters in the order shown below. For parameters that CSRIRP uses to obtain input values, assign appropriate values.

On entry to CSRIRP, register 1 points to the reference pattern service parameter list. Note that when a FORTRAN program calls CSRIRP, and it is running in access register (AR) mode, register 1 does not point to the reference pattern service parameter list; it points to a list of parameter addresses. Each address in this list points to the data in the corresponding parameter of the reference pattern service parameter list. To use reference pattern services in this environment, the caller must provide an assembler interface routine to convert the FORTRAN parameter list to the form expected by reference services.

Assign values, acceptable to CSRIRP, to low_address, size, direction, unitsize, gapsize, and units. CSRIRP returns values in return_code and reason_code.