HP Matrix Operating Environment Software User Manual
Page 151
Table 16 Units and Terminology (continued)
Measured in MB/s (10^6 bytes, megabytes per second).
Each sample represents an average reading over the past 5 minutes. These measurements are
obtained and calculated in the following manner:
Table 18 Data collection for disk I/O bandwidth utilization by platform
disk I/O bandwidth
utilization
Collected from
Calculation
Platform
pstat()
Total bytes transferred during the interval
HP-UX
/proc/diskstats
Total bytes transferred during the interval
Linux
WMI counter
Total bytes transferred out during the interval
Microsoft Windows
HP Virtual Machine
Management Pack
(VMM)
Imported as is
Proliant VM Host and
VMs
sys$getdvi
system
service DVI$_OPCNT)
Total bytes transferred during the interval
OpenVMS
Gigabytes. Unit used for memory: (10^9 bytes)
GBs
Gigahertz. In Capacity Advisor, CPU capacity is defined in terms of clock speed expressed in
megahertz (10^6 hertz) or gigahertz (10^9 hertz). Clock speed refers to the rate at which a
computer performs its most basic operations such as adding two numbers.
GHz
The difference between the average resource utilization on a system and the maximum available
capacity. See
for an explanation of headroom rating (stars), and
information on interpreting the star ratings shown in automated solutions.
headroom
Capability of some Intel processors to create an additional virtual core that provides additional
processing efficiencies. Note that Capacity Advisor does not count Hyper-Thread virtual cores
separately.
Hyper-Threading
In Capacity Advisor, the hypervisor includes not only the virtualization platform, but also all
functions performed by the host OS, as well as all virtual machine monitoring processes
(everything on the VM host that is not a VM guest).
hypervisor
Capacity Advisor estimates hypervisor memory overhead by adding together all memory used
in support of running guests. This overhead can be estimated by adding together the memory
use of the following:
hypervisor memory
overhead
•
the host operating system that the hypervisor is running on (HP-UX, Linux, Windows)
•
the hypervisor process that manages and enables the execution of guests
•
An overhead constant per guest that can either be a standard value for each guest on the
host, or a function of the amount of RAM allocated to a guest depending on the virtualization
platform.
Except in the case of HP Virtual Machine, Capacity Advisor assumes a worst case scenario
where all guests are allocated 1GB of memory, as this will maximize the hypervisor memory
overhead.
Megabits (10^6 bits) per second. Unit used for networking throughput.
Mb/s
Megabytes per second (10^6 bytes per second). Unit used for storage media throughput.
MB/s
The amount of memory used in gigabytes (2^30 bytes).
Each sample represents an actual reading at the time the sample was taken. These measurements
are obtained and calculated in the following manner:
Table 19 Data collection for memory utilization by platform
memory utilization
Collected From
Calculation
Platform
pstat()
Memory used by the users
HP-UX
/proc/stat
Memory used by the users
Linux
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