Show Vdisk-Statistics - HP P2000 G3 Cli Reference Manual

show vdisk-statistics

Description Shows live or historical performance statistics for vdisks. You can view live statistics for all or
specified vdisks, or historical statistics for a specified vdisk. The system samples disk-performance
statistics every quarter hour and retains performance data for 6 months.
The historical option allows you to specify a time range or a number (count) of data samples to
include. It is not recommended to specify both the time-range and count parameters; if both
parameters are specified, and more samples exist for the specified time range, the samples' values
will be aggregated to show the required number of samples.
For each vdisk these statistics quantify destages, read-aheads, and host reads that are cache misses.
For example, each time data is written from a volume's cache to disks in the vdisk that contains the
volume, the vdisk's statistics are adjusted.
Properties shown only in XML API format are described in
page 345.
NOTE:
higher in historical output than in live output. This is caused by a difference in the way that historical
and live values are calculated.
Live values are calculated based on the vdisk as viewed from the controller cache perspective. In the
live statistics, performance numbers are obtained by accounting for when data is written from cache
to disk or is read from disk to cache.
Historical data is obtained by using the summation of the disk statistics for the disks in the vdisk. The
historical vdisk data shows transfers to and from the disks in the vdisk that include the overhead of
any RAID transfers as well as any host activity.
Because I/Os from the RAID engine are included, values for the historical data appear higher than
the numbers for the live data.
Syntax To show live statistics:
show vdisk-statistics [vdisks]
To show historical statistics:
show vdisk-statistics
vdisk
historical
[time-range "date/time-range"]
[count number-of-data-samples]
[all]
Parameters vdisks
Optional. Identifies one or more vdisks to show live statistics for. If this parameter is omitted, statistics
will be shown for all vdisks. For vdisk syntax, see
vdisk
Identifies one vdisk to show historical statistics for. For vdisk syntax, see
page 22.
historical
Optional. Specifies to show historical statistics. If this parameter is omitted, live statistics will be
shown.
312 Alphabetical list of commands
Values for the amount of data transferred and for data throughput appear to be much
XML API basetype properties
Command syntax on page 22.
Command syntax
on
on