Zero fill is a form of over-the-wire compression. Agents do not send metrics to the Controller if the metrics value is 0. This keeps packet sizes smaller. The Controller keeps a record of metrics that were reported previously and when they were reported previously. Using this information, the Controller fills in metrics that weren't sent and have had data sent in the last 60 mins.
Zero-filling only happens when an agent is running and uploads metrics. If an agent goes down, there will be no zero-filling for the period the agent is down.
minor revision made to product capitalization.
C Landivar
