SFA counters

Use COUNTERS to show drive latencies

These commands will report physical disks and virtual disk latencies on DDN SFA controllers.  Other counters are available but this article highlight the physical disks (pd) and virtual disk (vd).

COUNTER behavior and usage

Each time this command is issued, the counters are reported and the counters are cleared.   The first time issuing the command from a login will report no previous counters and will start to cumulate, wait awhile and issue the command again will report the cumulated counts of that duration.  A long duration cumulation will require the user to be logged in.

show pd * counters all

show vd * counters all

Output examples

First time requesting counters from login, counters starts to cumulate:

RAID[0]$ show pd * count write_l
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
No previous counters of this type
Mon Sep 8 19:02:15 2014
RAID[0]$

A few minutes latesr, cumulated counters since last request:

RAID[0]$ show pd * count write_l

Physical Disk Write Latency:  Elapsed time = 299.833 seconds

  Idx      Avg    <=4ms    <=8ms   <=16ms   <=32ms   <=64ms  <=128ms  <=256ms  <=512ms     <=1s     <=2s     <=4s

------------------------------------------------------------------------------------------------------------------

  841        0        0        0        0        0        0        0        0        0        0        0        0

  842        0        0        0        0        0        0        0        0        0        0        0        0

  843       10        0     4034    15824      151       40        0        0        0        0        0        0 

  844        9        0     7524    12482       38        2        3        0        0        0        0        0

  845       12        0     2125    17017      552      344        3        8        0        0        0        0

  846        9        0     4987     9225       25        1        0        0        0        0        0        0

  847       27        0        1       15    18196     1816       21        0        0        0        0        0

  848       10        0     4112    15799      130        8        0        0        0        0        0        0

  849       11        0     1263    12694      277        3        0        0        0        0        0        0

  850       10        0     4321    15640       82        6        0        0        0        0        0        0

  851       12        0     2025    16946      737      327        6        8        0        0        0        0