The Agent Request Overflows alarm becomes active when a request for an agent was made after the limit for the MAXAGENTS database manager configuration parameter was reached. Once this limit is reached, the application begins to search for idle associated agents currently residing in the instance.
This alarm has been predefined with Low and Information severity levels. The underlying metric for this alarm can be adjusted to suit your environment by using the Metric Editor.
Try reducing the workload if the MAXAGENTS limit is exceeded on a regular basis.