QoS Limits causing high volume latency
Applies to
- ONTAP 9
- AFF Series
- FAS Systems
- CVO
- Quality of Service (QoS)
Issue
- Elevated LUN /volume/Qtree latency observed once QoS limits are reached
- As workloads change, QoS limits may need to be adjusted to help manage client performance expectations
- May see this alert from Active IQ Unified Manager: Event alert, Workload LUN latency threshold breached defined by Performance Service Level Policy
- The latency will be seen in the
QoS Max
column ofqos statistics volume latency show
:
::> qos statistics volume latency show -volume qostest -vserver testsvm
Workload ID Latency Network Cluster Data Disk QoS Max QoS Min NVRAM
--------------- ------ ---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
-total- - 646.73ms 1377.00us 0ms 262.00us 9.49ms 635.60ms 0ms 0ms
qostest-wid23.. 23350 646.73ms 1377.00us 0ms 262.00us 9.49ms 635.60ms 0ms 0ms
-total- - 634.31ms 1430.00us 0ms 263.00us 6.78ms 625.83ms 0ms 0ms
qostest-wid23.. 23350 634.31ms 1430.00us 0ms 263.00us 6.78ms 625.83ms 0ms 0ms
-total- - 640.86ms 1324.00us 0ms 304.00us 7.62ms 631.61ms 0ms 0ms
qostest-wid23.. 23350 640.86ms 1324.00us 0ms 304.00us 7.62ms 631.61ms 0ms 0ms
-total- - 659.83ms 1357.00us 0ms 303.00us 7.50ms 650.67ms 0ms 0ms
qostest-wid23.. 23350 659.83ms 1357.00us 0ms 303.00us 7.50ms 650.67ms 0ms 0ms