Note that your metric will likely be different than the above example. Highlighted is the standard message that you will see.
Duplicate or tardy metric value reported means one of the following:
1. That duplicate metrics were generated by duplicate instrumentation due to duplicate pbd files or some java scripts.
2. That there were some connectivity problem between the Agent and Collectors.
3. The EM is being overloaded.
Normally what happens is that the data is harvested from the Agent by the Collector. In this case, the data that was harvested by the Collector from the Agent matched the timestamp of the data from the previous time slice. The result is a WARN message indicating that we just received the same (duplicate) or late (tardy) data. This data is discarded and the EM continues processing data with a new time stamp.
This is typically due to a performance issue. To further investigate where the slowness occurred and what is contributing to it, open an issue with CA Support.