HP (Hewlett-Packard) XP12000 User Manual

26

Auto LUN XP for the XP12000/XP10000

Use the Chart Y Axis Rate list to select the highest value of the Y-axis (the vertical axis). This list is not 

displayed when the Plan button is active.
If you click the Detail check box, the graph displays detailed statistics. This check box is displayed when 

the Port-LUN or LDEV tab is active. The contents of the graph depend on the item selected in the list to the 

right of the table, as shown in the following table.

Table 9

Graph contents based on list selection (Port-LUN tab)

Selection in list

Graph contents

I/O Rate (number of I/Os per second)

•

Statistics in sequential access mode

•

Statistics in random access mode

•

Statistics in CFW (cache fast write) mode

•

If the read hit ratio or write hit ratio is high, random 

access mode is used for transferring data instead of 

sequential access mode. For example, random 

access mode might be used for transferring data to 

disk areas where Cache LUN XP is applied.

Read (number of read accesses per second)

1

1. Available only when I/O rates are displayed.

Write (number of write accesses per second)

1

Read Hit (read hit ratio)

Write Hit (write hit ratio)

Back Transfer (backend transfer: number of I/Os 

between the cache memory and disk drives)

•

Number of data transfers from the cache memory to 

disk drives

•

Number of data transfers from disk drives to cache 

memory in sequential access mode

•

Number of data transfers from disk drives to cache 

memory in random access mode

Trans. Rate (number of data transfers)

The graph does not display detailed information.