3PAR InForm® OS 2.3.1 CLI Administrator's Manual (320-200180 Rev B, February 2010)

12.6
Viewing Histograms
3PAR InForm CLI Administrator’s Manual InForm OS Version 2.3.1
Several filters are provided to refine the data output to display only data from specific
chunklets and logical disks,. Additional filters are provided to customize the way the
histogram data is displayed. Refer to the InForm OS Command Line Reference for complete
details about
histch command options and for sample command data output.
12.3.2 Viewing Histograms for Logical Disks
 To view histogram data for logical disks, issue the histld command.
The
histld command provides filters to refine the data output to display only data from
logical disks mapped to specific virtual volumes. Additional filters are provided to
customize the way the histogram data is displayed. Refer to the InForm OS Command Line
Reference for complete details about
histld command options and for sample command
data output.
12.3.3 Viewing Histograms for Physical Disks
 To view histogram data for physical disks, issue the histpd command.
Histogram data output can be further refined to display physical disk data from:
◆ a specific physical disk by either its ID or WWN.
◆ specific nodes.
◆ specific PCI slots.
◆ specific ports.
You can use additional filters to customize the way the histogram data is displayed. Refer
to the InForm OS Command Line Reference for complete details about
histpd command
options and for sample command data output.
NOTE: The Device Speed number does not represent a rotational speed for Solid
State Drives (SSD) without spinning media. It is meant as a rough estimation of
the performance difference between the drive and the other drives in the system.
For FC and NL drives, the number corresponds to both a performance measure
and actual rotational speed. For an SSD, the number is to be treated as a relative
performance benchmark that takes into account in I/O per second, bandwidth,
and the access time.