HP XP Array Manager Software - Manual (Page 82)

• Trans.: Indicates the size (in megabytes) of data transferred to the parity group, the external volume
group, or the volume per second.
• Read Hit: Indicates the read hit ratio.
• Write Hit: Indicates the write hit ratio.
• Back Trans.: Indicates the number of data transfers per second between the parity group (or the
external volume group, or the volume) and the cache memory.
• Response Time: This column indicates the time for replying from the parity group, the external
volume group, or the volume when I/O accesses are made from the host to them. The unit is milli-
seconds. The average response time in the period specified at Monitoring Term is displayed.
NOTE:
• For mainframe volume or the parity groups that contain mainframe volumes, the values of
Response Time are always 0.
• This column displays a hyphen (-) if the I/O rate is 0 (zero).
• CLPR: This column indicates numbers and names of CLPRs corresponding to each parity group,
external volume group, or volume in the format CLPR-number:CLPR-name. For details on CLPRs,
see HP StorageWorks XP24000/XP20000 Disk/Cache Partition User Guide.
Monitoring Ports
Performance Monitor monitors ports on the storage system and measures I/O rates (that is, the number
of I/Os per second) and transfer rates (that is, the size of data transferred per second). This section
describes how to view I/O rates and transfer rates of ports on the storage system. Before taking the
following steps, you need to start monitoring in accordance with the procedure described in “
Starting
and Stopping Storage System Monitoring ” on page 60 and obtain the usage statistics.
Performance Monitor can obtain statistics about traffics of ports connected to open-system host groups
only. The statistics about traffics of ports connected to mainframe host groups cannot be obtained.
Viewing I/O Rates for Ports
Performance Monitor monitors ports on the storage system and measures I/O rates (that is, the number
of disk I/Os per second).
To view I/O rates:
1. Ensure that the Auto LUN window is displayed.
2. Select the Port-LUN tab).
The tree displays a Subsystem folder.
3. Select the Subsystem folder.
The Target folder and the Initiator/External folder are displayed.
4. Select IOPS from the list on the right side of the window.
5. In Monitoring Term, do one of the following:
• To view the I/O rate in real time, you must select the Real Time option, specify the number
of recent collections of statistics which should be displayed in the graph, and then click Apply.
• To view I/O rates for a certain period of time in the last 24 hours, you must select the From
option, change the date and time in the From and To boxes, and then click Apply. Use the
arrow button and the sliders when you change the date and time in the From and To boxes.
Performance Monitor Operations 82