High NVRAM latency in Cloud Volumes ONTAP - Resolution Guide
Applies to
- ONTAP 9
- Cloud Volumes ONTAP (CVO)
Issue
- User workloads are slow to respond over any protocol (NAS or SAN)
- Latency is seen in
qos statistics volume latency show
under theNVRAM
::> qos statistics volume latency show Workload ID Latency Network Cluster Data Disk QoS NVRAM Cloud FlexCache SM Sync --------------- ------ ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- -total- - 195.97ms 150.00us 0ms 796.00us 0ms 0ms 1195.03ms 0ms 0ms 0ms data1-wid30897 30897 1.60s 157.00us 0ms 818.00us 0ms 0ms 1.60s 0ms 0ms 0ms -total- - 536.23ms 110.00us 0ms 495.00us 0ms 0ms 535.63ms 0ms 0ms 0ms data1-wid30897 30897 0ms 0ms 0ms 0ms 0ms 0ms 0ms 0ms 0ms 0ms -total- - 7.42s 136.00us 0ms 743.00us 0ms 0ms 7.42s 0ms 0ms 0ms data1-wid30897 30897 1137.67ms 1.65ms 0ms 3.55ms 0ms 0ms 1132.47ms 0ms 0ms 0ms
Example: On vol1, there was an increase in write workload which caused vNVRAM latency during that same time (after 12 AM on September 16, 2020)