Why do my application read/write metrics differ from Opscenters read/write metrics?

Summary

OpsCenter does a great job of showing latency readings for your cluster and your nodes. However understanding what these relate to is also important. 

Question

We are running an application which also records the read / write latency to and from our Cluster. However OpsCenter also shows latency times, how does this correlate to our application?

Answer

The diagram below shows where OpsCenter will measure its latency metrics

As can be seen from the diagram the users application will be measuring from a different point than OpsCenter, therefore there could well be a difference in the readings. For more details on the latency measurements and what each of them relate to please refer to the Official Datastax documentation on OpsCenter metrics here: http://www.datastax.com/documentation/opscenter/5.0/opsc/online_help/opscClusterPerformanceMetrics_r.html