Sample Virtual Disk Statistics Display; Hp Command View Evaperf Virtual Disk Statistics - HP 6100 Software Manual

Figure 6 Sample virtual disk statistics display
.
Table 3 HP Command View EVAPerf virtual disk statistics
Counter
Read Hit Req/s
Read Hit MB/s
Read Hit Latency
Read Miss Req/s
Read Miss Data Rate
Read Miss Latency
Write Req/s
Write Data Rate
Write Latency
Flush Data Rate
28 Pre-upgrade tasks
Description
The number of read requests per second completed from the array cache
memory. Data may reside in the cache memory due to a previous cache miss
or because of a prefetch operation generated by a sequential read data stream.
The rate at which data is read from the array cache memory because of read
hit requests.
The average time it takes to complete a read request (from initiation to informa-
tion receipt) from the array cache memory.
The number of read requests (per second) that failed to complete from the array
cache memory and were completed from physical disks instead.
The rate at which data is read from physical disks because the data was not
present in the array cache memory.
The average time it takes to complete a read request (from initiation to informa-
tion receipt) from the physical disks.
The number of write requests per second completed to a virtual disk that were
received from all hosts. Write requests may include transfers from a source array
to this array for data replication and host data written to snapshot or snapclone
volumes.
The rate at which data is written to the virtual disk by all hosts and includes
transfers from the source array to the destination array.
This average time it takes to complete a write request (from initiation to receipt
of write completion).
The rate at which data is written to a physical disk for the associated virtual
disk. The sum of flush counters for all virtual disks on both controllers is the rate
at which data is written to the physical drives and is equal to the total host write
data. Data written to the destination array is included. Host writes to snapshots
and snapclones are included in the flush statistics, but data flow for internal
snapshot and snapclone normalization and copy-before-write activity are not
included.