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Question about qos statistics output

Hello,

I'm in the process of testing QoS functionality and I really like the "qos statistics performance show" & "qos statistics workload performance show" commands for the data they provide.

However, the output truncates the object names (either the policy group or object name) after 18 characters and I don't see any option for the qos statistics command that will permit me to specify the policy group or workload (object).

I'm concerned about this because in our environment it's possible to have volume names that aren't unique until after the 18th character.  How would I know what object I'm looking at if I can't specify the group or object names against the command?

Thanks.

-Dave

Re: Question about qos statistics output

This question is broken into two parts for response.

I. QoS statistics workload's 18 character output restriction

Workaround summary: In Data ONTAP 8.2.x version, two step workflow with "qos workload performance show" and diagnostics privilege "qos workload show" commands can  be used to identify the workload ID of the object and map to the object uniquely using the identified workload ID.

Workflow Details:

(1) Use "qos statistics workload performance show" to list the top 20 workloads. Use the ID column's value for identifying the workload's unique ID.

E.g.

  clus-sparab2::*> qos statistics workload performance show

Workload            ID     IOPS       Throughput    Latency

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

-total-              -      472        15.15MB/s    10.09ms

_USERSPACE_APPS     14      279         5.32MB/s     7.70ms

vs0_vol123244..   8195      158         9.83MB/s    16.57ms         <=== too long of a volume name, but with a unique workload ID.

Workload id of "vs0_vol123244.." workload is 8195

(2) Set diagnostic privilege to use diagnostic level:"qos workload show" command for listing workload information. Then Use "qos workload show" command's  "-wid" option to list workload

information.

E.g. clus-sparab2::*> qos workload show -wid 8195

Workload       Wid   Policy Group Vserver  Volume   LUN    Qtree  File

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

vs0_vol1232443545466565-wid8195

                8195  pg1          vs0      vs0_vol1232443545466565  <== complete name of the workload

                                                     -      -      -

II.  20 row limitation of qos statistics CLI.

There is no way to adjust this.  The "qos statistics" UI was designed to be a quick way to show the top-20 workloads that are impacting the system.  For regular monitoring of all the

work on a cluster, a better approach is to write a script to send ZAPIs to collect all the performance data.  The data shown by "qos statistics" isn't directly available, but with some math, the same performance characteristics can be calculated.

Re: Question about qos statistics output

Also in order to avoid truncation of names you could use the following commands : set –showallfields true or set -showallfields true -showseparator ","

BEFORE: truncated names

clus-sparab::*> qos statistics performance show

Policy Group IOPS      Throughput    Latency

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

-total- 6066        5.76MB/s   810.00us

_System-Best-Effort 6044        5.67MB/s   811.00us

toolonganame123456.. 21       85.33KB/s   468.00us

-total- 6478      216.42KB/s   649.00us

_System-Best-Effort 6456      131.09KB/s   649.00us

toolonganame123456.. 21       85.33KB/s   781.00us

-total- 5810        2.86MB/s   758.00us

_System-Best-Effort 5789        2.78MB/s   753.00us

toolonganame123456.. 21       85.33KB/s     2.06ms

AFTER: full names

clus-sparab::*> set -showallfields true -showseparator ","

clus-sparab::*> qos statistics performance show policy-group,iops,tput,latency,

Policy Group, IOPS,     Throughput,   Latency,

-total-,5838,2.65MB/s,802.00us,

_System-Best-Effort,5817,2.56MB/s,776.00us,

toolonganame12345678901234567891,21,85.33KB/s,7.85ms,

-total-,7674,165.95KB/s,547.00us,

_System-Best-Effort,7653,79.29KB/s,521.00us,

toolonganame12345678901234567891,22,86.67KB/s,9.85ms,

-total-,7670,171.32KB/s,547.00us,

_System-Best-Effort,7648,84.65KB/s,521.00us,

toolonganame12345678901234567891,22,86.67KB/s,9.85ms,

regards

Amrita