HP XP Performance Advisor Software - Manual (Page 324)

4. Click
Stop Plotting.
The
real-time data collection stops and the record removed from the list for the selected XP
or
XP7 disk array.
Troubleshooting using host group or WWN
Introduction
HP
XP7 Performance Advisor helps identify bottlenecks in the performance of applications that
reside
on hosts and use the XP and the XP7 disk arrays for storing their data. The hosts are
identified
using their host groups or WWNs. These hosts might not have HP XP7 Performance
Advisor
host agents installed.
NOTE:
•
In
this context, the term 'application' does not include HP XP7 Performance Advisor. It refers
to
applications that reside on hosts and use the XP and XP7 disk arrays to store data. HP
XP7
Performance Advisor helps you identify issues in the performance of such applications.
An application's response to user requests is determined by the performance of all the associated
LDEVs, which is attributed to the time taken by the LDEVs to process requests. Higher response time
from the LDEVs leads to increase in response time from the applications to user requests. Further,
an LDEV's response time is based on components associated with that LDEV.
If your application is associated with components that belong to the XP disk arrays, the response
time of an LDEV is determined by the performance of the following components that are associated
with that LDEV:
•
Ports (Frontend components)
•
CLPRs (Cache)
•
RAID groups (Backend components)
If
your application is associated with components that belong to the XP/XP7 disk arrays, in
addition
to the above-mentioned components, an LDEV's response time is also determined by the
average
utilization of the associated MP blades.
The
performance data of the LDEVs, ports, CLPRs, RAID groups, and the usage data of the MP
blades
(applicable for the P9500/XP7 disk arrays) is displayed on the Troubleshooting screen
( “Host
Based Troubleshooting Screen” (page 325)
)
for a prominent set of metrics that HP XP7
Performance
Advisor supports. In addition, select additional metrics and view the performance
data
for these components. Analyzing performance metrics of LDEVs and the associated components
help
you to identify the component that is resulting in the application's high response time, which
further
enables you to take the necessary corrective action, such as load balancing across
components.
For example, one of the reasons for an application's high response time can be
attributed
to the heavy IOPS on the port, which is servicing requests to multiple LDEVs associated
with
different applications.
IMPORTANT:
•
An
application can reside on multiple hosts that connect to the XP and the XP7 disk arrays.
•
A
host group can have multiple WWNs to connect to an XP or an XP7 disk array.
•
The data displayed on the Troubleshooting screen only enables your analysis of the issue and
arriving at a probable solution. This screen does not provide a resolution for the issue.
324 Troubleshooting issues for components associated with applications