Administrator Guide

Table 28. Historical performance
System component Graph Description
Disk, group, pool, tier Total IOPS Total number of read and write
operations per second since the last
sampling time.
Disk, group, pool, tier Read IOPS Number of read operations per second
since the last sampling time.
Disk, group, pool, tier Write IOPS Number of write operations per second
since the last sampling time.
Disk, group, pool, tier Data Throughput Overall rate at which data was read and
written since the last sampling time.
Disk, group, pool, tier Read Throughput Rate at which data was read since the
last sampling time.
Disk, group, pool, tier Write Throughput Rate at which data was written since the
last sampling time.
Disk, group, pool, tier Total I/Os Number of read and write operations
since the last sampling time.
Disk, group, pool, tier Number of Reads Number of read operations since the last
sampling time.
Disk, group, pool, tier Number of Writes Number of write operations since the
last sampling time.
Disk, group, pool, tier Data Transferred Total amount of data read and written
since the last sampling time.
Disk, group, pool, tier Data Read Amount of data read since the last
sampling time.
Disk, group, pool, tier Data Written Amount of data written since the last
sampling time.
Disk, group Average Response Time Average response time for reads and
writes since the last sampling time.
Disk, group Average Read Response Time Average response time for reads since
the last sampling time.
Disk, group Average Write Response Time Average response time for writes since
the last sampling time.
Disk, group Average I/O Size Average size of reads and writes since
the last sampling time.
Disk, group Average Read I/O Size Average size of reads since the last
sampling time.
Disk, group Average Write I/O Size Average size of writes since the last
sampling time.
Disk, group Number of Disk Errors Number of disk errors since the last
sampling time.
Disk, group Queue Depth Average number of pending I/O
operations being serviced since the last
sampling time. This value represents
periods of activity only and excludes
periods of inactivity.
Pool, tier Number of Allocated Pages Number of 4-MB pages allocated to
volumes, based on writes to those
volumes. Creating a volume does
136 Working in the Performance topic