Common Misconfigured HP-UX Resources (April 2006)

Overview
Physical memory is a finite resource. It is also a shared resource with many processes attempting to
access this finite resource. Not only do processes need memory in order to run, the HP-UX operating
system (or kernel) also needs spaces for its critical resources and tables. Some of these resources are
static (do not change in size) and some are dynamic. Many of these resources can be configured to
be a certain size or configured to be limited by a certain value.
While there are many possible system resources that can take up memory, this document attempts to
identify some of the common misconfigured HP-UX resources and how they impact your system.
There are many reasons why an HP-UX resource may be misconfigured. The most common reason is
that customer environments are unique. There is no one set of tunables that is best for all systems.
Understanding how these resources are managed and how they impact memory utilization is key to a
successful configuration.
This document discusses the following topics:
• The HFS Inode Cache
• The HP-UX Buffer Cache
• The JFS Inode Cache
• The JFS Metadata Buffer Cache
• Semaphores Tables
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