QIO Configuration and Management Manual

QIO Configuration and Management Manual—424717-008
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Configuring the QIO Subsystem
This section describes custom configuration of the QIO subsystem on a NonStop
S-series server and on an Integrity NonStop NS-series server.
Overview
The default configuration of QIO is set to maximize QIO memory availability. However,
the default configuration sacrifices memory space available to applications. Read this
section to determine whether you should keep the default configuration or configure
QIO differently. This section also provides procedures for changing the default
configuration.
Starting with the G06.17 RVU, QIO has four configuration parameters that you can use
to tailor QIO to your environment. The four options are discussed in Before You Begin
on page 2-6.
Assumptions
The following discussions assume that you are familiar with how flat memory space is
allocated, the structure and uses of system data space, and the demands on your
user-addressable data space.
For more information refer to the following manuals:

SCF Reference Manual for the Kernel Subsystem

NonStop S-Series Server Description Manual

Guardian Programmer’s Guide
Note. System data space refers to Kseg2 memory space for NonStop S-series servers and to global
privileged space for Integrity NonStop NS-series servers. Kseg2 still appears in displays, for backward
compatibility, on the Integrity NonStop NS-series server.