lun latency increasing

[BrendonHiggins]

I have a lun which holds the SQL data file and it is showing increased lun latency.

The data is from this month's monthly report for storage, shows LUN latency increasing for the database data file LUNs.  Past experience has shown, users become affected at about the 11 ms mark and action should be taken to avoid this scenario.  So a NetApp support case was opened to try and address the performance issue.

How do I show if this is a caching or fragmentation issue?  I have been looking through the prefstat reports and verything looks healthy apart from the latency.  Not sure what "cp_dirty_allocation_blks" is but it is 1000+

Read Write   Read  Write Average   Queue  Lun
  Ops   Ops     kB     kB Latency  Length
    0     0     32      0    7.54    0.07 /vol/sqf02/diskf.lun
    0     0     37      0    7.00    1.00 /vol/sqf02/diske.lun

Read Write   Read  Write Average   Queue  Lun
  Ops   Ops     kB     kB Latency  Length
    1     0     80      0   11.31    0.08 /vol/sqf02/diskf.lun
    2     0    123      0   10.96    0.08 /vol/sqf02/diske.lun

CPU   NFS  CIFS  HTTP   Total    Net kB/s   Disk kB/s     Tape kB/s Cache Cache  CP   CP Disk    FCP iSCSI   FCP  kB/s iSCSI  kB/s
                                  in   out   read  write  read write   age   hit time  ty util                 in   out    in   out
20%     0  1541     0    2140   376  5881  12354   7140     0     0    19   94%  16%  F   28%    595     2  9228  5290     1     0
26%     0  1162     0    2172   498  3993  14646  20264     0     0    18   95%  39%  3f  31%   1006     2 18393  8112     1     0

lun:sqf02/diske.lun-XXXXZZZZZ:display_name:/vol/sqf02/diske.lun
lun:sqf02/diske.lun-XXXXZZZZZ:read_ops:0/s
lun:sqf02/diske.lun-XXXXZZZZZ:write_ops:2/s
lun:sqf02/diske.lun-XXXXZZZZZ:other_ops:0/s
lun:sqf02/diske.lun-XXXXZZZZZ:read_data:36798b/s
lun:sqf02/diske.lun-XXXXZZZZZ:write_data:19872b/s
lun:sqf02/diske.lun-XXXXZZZZZ:queue_full:0/s
lun:sqf02/diske.lun-XXXXZZZZZ:avg_latency:22.17ms   <-------------------- Why?
lun:sqf02/diske.lun-XXXXZZZZZ:total_ops:3/s
lun:sqf02/diske.lun-XXXXZZZZZ:scsi_partner_ops:0/s
lun:sqf02/diske.lun-XXXXZZZZZ:scsi_partner_data&colon;0b/s
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.0:98%
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.1:0%
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.2:0%
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.3:0%
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.4:0%
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.5:0%
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.6:0%
lun:sqf02/diske.lun-XXXXZZZZZ:read_align_histo.7:0%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.0:86%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.1:0%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.2:0%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.3:0%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.4:0%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.5:0%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.6:0%
lun:sqf02/diske.lun-XXXXZZZZZ:write_align_histo.7:0%
lun:sqf02/diske.lun-XXXXZZZZZ:read_partial_blocks:1%
lun:sqf02/diske.lun-XXXXZZZZZ:write_partial_blocks:13%

Thanks ifyou know the answer

Bren