After changing the SNMP Timeouts/Retries as well as the maxrequestsize, we are still receiving the Data Collector Dropped Poll Request events
The devices in question had too many polled items to be able to poll within the default 5 min poll time.
All supported releases
There are two further items you can try to allow the device to poll fully:
1. Alter the Metric Families assigned to the device to only associate the ones that you need the data from.
2. Increase the poll frequency higher than the default 5 min to allow more time to poll the device.