topic Re: Can QoS for IOPS be applied or assigned to a Volume that is being accessed by the client ? in ONTAP Discussions

Can QoS for IOPS be applied or assigned to a Volume that is being accessed by the client ?

Ontapforrum — Wed, 04 Jun 2025 12:49:32 GMT

Hi All,

Can QoS be appied (For max IOPS) dynamically ? While the clients are accessing the volume be it CIFS or NFS ?

Do I need to stop the CIFS service or NFS service first, and then apply the QoS IOPS Policy, and reestart the Protocol service ?

In a simple simulator test on ONTAP 9.4 : I was copying a large file, and it was consuming most of the IOPS available to it. When I assigned QoS policy for [100 IOPS}, it did not ahered to it.

However, once the copy was over, I re-assigned the Policy (IOPS 100) and started another copy and this time I could see constant IOPS of 110. I did not have to stop the CIFS service, as this is a SIMULATOR and I knew it's just one activity, so it was simple.

Does anyone has more insight ?

Thanks,

-Ash

Re: Can QoS for IOPS be applied or assigned to a Volume that is being accessed by the client ?

SpindleNinja — Mon, 18 Feb 2019 23:15:53 GMT

You do not need to stop either service to apply QoS to objects.

I wouldn't gague throughput on a simulator... Build yourself a test SVM on your cluster and work with it there if you can.

Re: Can QoS for IOPS be applied or assigned to a Volume that is being accessed by the client ?

Ontapforrum — Mon, 18 Feb 2019 23:38:44 GMT

Simulator is a great tool for proving the concept, and it works very well. I am not testing the IOPs gauge here, period. it is simple question whether it can be applied dynamically or not. Does anyone have any document reference that says it can be applied while the volume is in use byvthe clients.

Re: Can QoS for IOPS be applied or assigned to a Volume that is being accessed by the client ?

paul_stejskal — Tue, 19 Feb 2019 15:31:25 GMT

Yes it takes place the minute you apply to a volume, LUN, file, or SVM. https://www.netapp.com/us/media/tr-4211.pdf has some info on it starting on page 17.