Machine pool size requirements

The machine memory pool is used for highly-shared machine and operating system programs. The machine memory pool provides storage for jobs the system must run that do not require your attention. If you set the size for these storage pools too small, you will impair system performance. You cannot set QMCHPOOL to less than 256 KB. The size for this memory pool is specified in the machine memory pool size system value (QMCHPOOL). No user jobs run in this memory pool.

Start of change All supported IXS and IXA attached integrated server hardware requires a minimum 856KB of memory. For information about iSCSI attached server memory requirements, see iSCSI install read me first Link outside the Information Center. . End of change

You can display or change the machine pool size by using the Work With System Status (WRKSYSSTS) command. The first storage pool on the WRKSYSSTS display is the machine pool.

You can change the system value QPFRADJ so that the system automatically adjusts system pool sizes. However, because automatic performance adjustment can slow down a busy system, you probably want to limit its use to one of these times:

The first couple days after the installation
An hour or so at the time your system load changes from daytime (interactive emphasis) to nighttime (batch emphasis) and back