HP XP Array Manager Software - Manual (Page 23)

• User types
If the user type of your user ID is storage partition administrator, the functions you can use are
limited. For details, see “ Storage Partition Administrators Limitations ” on page 25.
• Powering off the storage system
If you power off the storage system during monitoring, monitoring stops only while the storage
system is powered off. When you power on the storage system again, Performance Monitor
cannot display the monitoring data while the storage system is powered off. The monitoring data
immediately after powering on again might contain extremely large values.
• Viewing the Physical tab
• You will be able to view usage statistics that have been obtained for the last three months (that
is, 93 days) in long-range monitoring, and for the last 15 days in short-range monitoring. You
will not be able to view usage statistics that expired after these storing periods because such
statistics are erased from the storage system.
• In short range, if I/O workloads between hosts and the storage system become heavy,
the storage system gives higher priority to I/O processing than monitoring processing,
therefore, a part of monitoring data might be missing. In case that monitoring data are
missing frequently, use the Gathering Interval option in the Monitoring Options window to
change the collection interval longer. For details, see “ Start Monitoring ” on page 47 and
“ Monitoring Options Window ” on page 42.
• Short-range monitoring data and long-range monitoring data may have some margin of error.
• Viewing the LDEV, Port-LUN, and WWN tab
• Monitoring results are stored for the last 8 hours to 15 days depending on the specified
gathering interval. If the storing period have passed since a monitoring result was obtained,
the result is erased from the storage system and you will not be able to view that monitoring
result.
• If I/O workloads between hosts and the storage system become heavy, the storage system gives
higher priority to I/O processing than monitoring processing, therefore, a part of monitoring
data might be missing. In case that monitoring data are missing frequently, use the Gathering
Interval option in the Monitoring Options window to change the collection interval longer. For
details, see “ Start Monitoring ” on page 47 and “ Monitoring Options Window ” on page 42.
• Displaying monitoring data
• In lists of the Auto LUN window contents, a hyphen (-) might be displayed in monitoring data
columns. It means that the statistics of that monitoring item cannot be collected.
• If the SVP is overloaded, more time than the gathering interval allots might be required for
updating the display of monitoring data. In this case, some portion of monitoring data will not
be displayed in the window. For example, suppose that the gathering interval is 1 minute.
In this case, if the display in the Auto LUN window is updated at 9:00 and the next update
occurs at 9:02, the window (including the graph) does not display the monitoring result for the
period of 9:00 to 9:01. This situation occurs when you use a Remote Web Console computer,
as well as when the SVP is used to perform maintenance operations for the DKC.
• Replacing the micro program
After the micro program was replaced, the monitoring data is not stored until a service engineer
releases the SVP from Modify mode.
XP24000 Performance Monitor User's Guide 23