The second requirement is that the system must be able to process and write the data to the repository at the average data rate of the combined sources. Writing can proceed at the average rate as long as there is enough memory to buffer short bursts at the peak rate.
You might specify a desired frame rate for updating the display of the data. However, there is usually no real-time requirement on display rate for a data collection system. That is, the system is correct as long as it receives and stores all data, even if the display is updated slowly.