gtps4m0s | System Generation |
The control program records and table area in main storage is allocated and partially initialized by the control program initializer (CCCTIN) as part of the restart procedure. CCCTIN uses information contained in system keypoint records. These keypoints are generated by SIP based upon user input data provided via the SIP macros.
Numerous tables and data records are contained in this area. SIP Stage II calculates the size of each table and outputs the total size of the entire control program and table area as part of the SIP-created macro SKGTSZ.
Various records and tables are discussed in many of the later sections of this document. For example, in the sections concerning communications support (Data Communications Support) there is a discussion of the particular requirements of those functions upon this area. The user is advised to read all of these sections prior to making the estimate. The alternative is to use the SIP report which results from the execution of Stage I. The user must also be aware of the effects of activating the SNA support which is accomplished by updating the SNAKEY macro in the SNA communications keypoint (CTK2).
In addition to the other records and tables, which are discussed in later sections, there are several that can now be considered.
The record hold table is a set of 2 tables (primary and overflow) containing 16-byte entries used for controlling the record hold facility. This facility allows an entry block exclusive use of a record. Both tables reside in the control program records and table area and are allocated by the initializer program. SIP provides the PHTBL and the OHTBL parameters of the RAM macro to specify the number of primary and overflow tables entries respectively.