Reference Guide

ZCOM Tables and Data Structures
ZCOM Header Structure
Chapter 346
This pointer contains the starting physical kernel memory address of the
ZCOM subsystem memory. It is initialized to zero by TTGEN. ZMON
initializes it with the memory address while loading the memory tables
into kernel memory. It is a 64-bit value when used in a 64-bit kernel.
HSSIZE - Total runtime system size in bytes
This is the total size in bytes of the ZCOM subsystem memory, including
all tables, queue headers, and the buffer pool.
HBPSIZE - Buffer pool size in bytes
This is the size in bytes of the ZCOM buffer pool. It is defined by the
Buffer-Pool parameter in the TTGEN configuration file.
HNDMAX - Number of node entries
This contains the maximum number of node entries which may exist in
the node entries memory section. This value is defined by the Node-Entry
keyword in the TTGEN configuration file. Each Local-Node and
Remote-Node definition consumes one node table entry.
HZLMAX - Total number of ZLUs
Total number of terminal ZLUs and spare (i.e., program) ZLUs. That is,
this is the combined values of the Program-ZLU and Terminal-ZLU
parameters specified in the TTGEN configuration file.
HTMZLU - Number of terminal ZLUs
This is the number of ZLUs out of the total (HZLMAX) that are allocated
to terminals. The terminal ZLU numbers are allocated from 1 up to the
number specified in this field. The TTGEN Terminal-ZLU parameter is
used to initialize this field.
HSPZLU - Number of program ZLUs
Total number of available program ZLUs. The TTGEN Program-ZLU
parameter is used to initialize this field.
HSPZL1 - First program ZLU number
Number of the first ZLU not allocated to terminal ZLUs. This field is
initialized to the value of the TTGEN parameter Terminal-ZLU + 1. It
indicates where the program ZLUs begin within the ZLU Table. Note
that program ZLUs are assigned from the range (Terminal-ZLU+1) to
(Terminal-ZLU + Program-ZLU).