Avago Technologies 3ware 9650SE-12ML (Channel) - Manual (Page 266)

Troubleshooting
254 3ware SAS/SATA RAID Software User Guide, Version 9.5.1
• Display a DPM Summary . This shows whether DPM is On or Off, and
provides summary statistics for drives attached to a controller.
(/cx show dpmstat)
Note that if DPM is Off, this summary may still show data, although that
data will be static, and not changing over time. Disabling DPM does not
clear the existing data. That is done separately, on a per-port basis (see
below.)
You can also show a subset of summary data, for individual types of
statistics (instantaneous, running average, or extended drive statistics), by
specifying a type attribute with the command.
• Display Specific Drive Statistic . On a per-port basis, you can display
five different statistical reports:
• Instantaneous. This measurement provides a short duration average.
(/cx/px show dpmstat type=inst)
• Running Average. Running average is a measure of long-term
averages that smooth out the data, and results in older results fading
from the average over time (/cx/px show dpmstat type=ra)
• Long Command Times. This a collection of the commands with the
longest read/write response time. (/cx/px show dpmstat type=lct
• Histogram Data. The histogram categorizes the read/write execution
times and group them together based on time frames.
(/cx/px show dpmstat type=histdata)
• Extended Drive Statistics. The extended drive statistics refers to
statistics of a drive's read commands, write commands, write
commands with FUA (Force Unit Access), flush commands, and a
drive sectors's read, write, and write commands with FUA.
(/cx/px show dpmstat type=ext)
• Clear Individual Statistic Counters. On a per-port basis, you can clear
specific statistic counters, using these commands:
• /cxpx set dpmstat=clear
• /cxpx set dpmstat=clear type=ra
• /cxpx set dpmstat=clear type=lct
• /cxpx set dpmstat=clear type=ext