Quality of Service limit is not enforced
Applies to
ONTAP 9
Issue
- Quality of Service limit is not enforced when using a maximum (ceiling) limit of IOPS and throughput (MB/s), in addition to a minimum (floor) limit
- A higher limit of MB/s is allowed than the policy is configured for
Example: A QoS policy is set to 4000IOPS, 300 MB/s max with a floor of 200 IOPS yet is only getting limited at 4000 IOPS but not 300 MB/s
Cluster::> vol show -volume vol1 -fields qos-policy-group
vserver volume qos-policy-group
------- ------ ----------------
svm1 vol1 qos-policy-1
Cluster::> qos policy-group show -policy-group qos-policy-1
Policy Group Name: qos-policy-1
Vserver: svm1
Uuid: 12345678-9012-3456-7890-123456789012
Policy Group Class: user-defined
Policy Group ID: 11948
Maximum Throughput: 4000IOPS,300MB/s
Minimum Throughput: 200IOPS
Number of Workloads: 1
Throughput Policy: 200IOPS-4000IOPS,300MB/s
Is Shared: true
Is Policy Auto Generated: -
cluster::> qos statistics volume performance show -volume vol1 -vserver svm1
Workload ID IOPS Throughput Latency
--------------- ------ -------- ---------------- ----------
-total- - 4097 1111.90MB/s 216.87ms
vol1-wid104 104 3995 1111.75MB/s 412.78ms
cluster::> qos statistics workload latency show -volume vol1 -vserver svm1
Workload ID Latency Network Cluster Data Disk QoS Max QoS Min NVRAM Cloud FlexCache SM Sync VA
--------------- ------ ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
-total- - 48.38ms 3.04ms 48.00us 717.00us 125.00us 17.09ms 0ms 2.00us 0ms 0ms 0ms 0ms
vol1 104 464.73ms 19.72ms 0ms 57.00us 14.00us 444.44ms 0ms 1.00us 0ms 0ms 0ms 0ms