HP Capacity Advisor 7.2 User Guide

Units and terminology
The units and terms listed in the following table are used within Capacity Advisor. For an expanded
list of terminology used within Capacity Advisor and Matrix OE, see the “Glossary” at the end of
this guide.
Table 31 Units and Terminology
MeaningUnit or Key Word
Some newer processors are capable of short bursts of speed above the base speed of the
processor. When Capacity Advisor shows the clock speed of a system, it reports the base speed.
Some other applications (such as the Onboard Administrator) may report the maximum clock
speed. Integrated Lights Out software reports both the base and accelerated (maximum) clock
speed.
Processors are also able to run at slower clock speeds to save power. These different
power/performance states are called P-states, with the fastest P-state called “P0”. When Capacity
Advisor shows the clock speed of a system, it gives the P0 clock speed, as opposed to the current
clock speed.
clock speed
Active data-processing unit within a processor; a processor (CPU) can contain one or more
cores. Multiple cores on the same physical unit provides the capability for multiprocessing within
the same CPU.
core
Central Processing Unit. The computer chip that executes most programming instructions; can
be composed of one or more cores.
CPU
The number or percentage of CPU cores in use.
Each Capacity Advisor data sample represents a five-minute average of CPU cores used over
that period of time. These measurements are calculated by tracking CPU usage within the kernel
at each polling interval in the following manner:
Table 32 Data collection for CPU utilization by platform
Collected FromCalculationPlatform
pstat()Total used CPU ticks during the interval
divided by the total available CPU ticks
during the interval
HP-UX
/proc/statTotal used CPU ticks during the interval
divided by the total available CPU ticks
during the interval
Linux
WMI counterPercent busy since the start of the intervalMicrosoft Windows
HP Virtual Machine
Management Pack
(VMM)
Imported as isProliant VM Host and
VMs
CPU database CPU
tick counters
Total used CPU ticks during the interval
divided by total available CPU ticks during
the interval.
OpenVMS
When monitoring user-defined workloads, CPU and memory utilization for short-lived,
"user-owned" processes may be missed. Short-lived processes are those lasting less than five
minutes that span less than two sample periods. Any "missed" utilization is attributed to system
processes.
CPU utilization
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