Slow read operations, latency, or loss of access due to outage in a FabricPool volume

Applies to

• ONTAP 9
• FabricPool
• StorageGRID

Issue

• High latency reported for read operations while reading the data from the cold tier.
• Latency may cause outages or loss of VM access. 
• Latency is seen in Cloud column of qos statistics volume latency show.

::> qos statistics volume latency show -volume vol1 -vserver svm1
Workload            ID    Latency    Network    Cluster       Data       Disk        QoS      NVRAM      Cloud  FlexCache    SM Sync
--------------- ------ ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
vol1              8036    32.21ms   797.00us     2.00us     3.38ms    52.00us        0ms        0ms    27.98ms        0ms        0ms
vol1              8036    31.06ms   711.00us     5.00us     2.70ms    15.00us        0ms        0ms    27.63ms        0ms        0ms