5-30 Performance Monitor Operations
Hitachi Universal Storage Platform V/VM Hitachi Performance Manager User’s Guide
Read: Indicates the number of read requests to the parity group, the
external volume group, or the volume per second.
Write: Indicates the number of write requests 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 milliseconds. The average
response time in the period specified at Monitoring Term is displayed.

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 the Virtual Partition
Manager User's Guide.
Viewing Transfer Rates for Disks
Performance Monitor audits hard disk drives and measures transfer rates (that
is, the size of data transferred in one second).
To view transfer rates:
1. Ensure that the Performance Management window is displayed.
2. Click the LDEV tab.
The tree displays a list of parity groups and external volume groups.
3. Select MB/s from the list on the right side of the window.
4. In the tree, do one of the following:
To view the transfer rate for each parity group and external volume
group, select the Subsystem folder or a Box folder.
The list on the right displays the transfer rate for each group.