High latency can be caused by a lot of factors; over utilized disks, CPU, congested network, etc
Though SCOM/MyAutosupport/OCUM could give some information, the best analysis would be to collect stats with the Perfstat tool and let NetApp analyze it
- there are plenty of ONTAP commands to show performance but you have to understand how to interpurt them
- 5 ms latency is not bad. Even for the most sensitive applications