HP XP Performance Advisor Software - Manual (Page 361)

NOTE: The backend transfer is the block of data that is transferred between the XP or the P9000
disk array cache and the RAID groups. Every read cache miss results in a backend transfer.
A sample of each report is given below:
Total I/O Rate report
The Total I/O Rate report displays in a chart format, the number of total read and write I/O
operations over the entire period.
“Total I/O Rate” (page 362) displays a sample Total I/O Rate
report for the P9500 Disk Array.
Report types 361