PRM Product Overview

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• Enables you to create Secure Resource Partitions, which combine HP-UX 11i v2 security capabilities
with the resource management capabilities of PRM
• Can scan UNIX® accounting files for data on the specified resource (CPU, real memory, and disk
I/O bandwidth) and then order the accounting records by user, UNIX group, command name, or
PRM group (This feature helps in better understanding resource usage for capacity planning
purposes and for fine-tuning resource allocation configurations.)
Comparing HP Process Resource Manager and HP-UX
priorities and “nice” features
You could ask the question, “Why do I need PRM when HP-UX has the ability to assign different
priorities and different ‘nice’ values to processes?”
The answer is simple. Both of these HP-UX features help influence an application’s access to CPU
resources, but neither of these two HP-UX features enables an application to have a guaranteed
percentage of the system (CPU resources). With PRM, an application can be guaranteed a configured
CPU allocation and other critical system resources.
Standard HP-UX scheduler
How does CPU allocation work under the standard UNIX scheduler?
When the standard UNIX CPU scheduler is in effect, all processes compete with each other for CPU
time. In this case, low-priority applications can affect the performance of higher priority applications.
Because the standard CPU scheduler attempts to share CPU cycles equally among all processes, it is
not possible to guarantee that business priorities will be achieved for critical applications. Figure 1
illustrates the situation in which one user is consuming most of the available CPU resource by
executing two applications.
Figure 1. Standard UNIX CPU scheduler
Because the CPU time is allocated equally to the executing processes, each application receives 33%
of the available CPU resource. However, equality is not always a desired characteristic. Application