Devices in "catch-up" mode
Documentation for the Wattwatchers API
V1.1.0 last updated 4 months ago on 2020/04/24
It's important to note that "Internet of Things" (IoT) applications are not like traditional computer systems in terms of data delivery. They are susceptable to communications outages and other issues that may delay the transmission of data from the device to the Wattwatchers infrastructure, and thus what is available via the API at any point in time.
Similarly, while we work very hard to ensure that our systems work flawlessly, 24/7, there are occasions where delays may be introduced within the Wattwatchers system, for example a short lag after a system maintenance window.
In such cases, data may delayed from being available from devices.
There are circumstances where a device may continue to collect data but be unable to transmit that data to the Wattwatchers system for a period. When the device re-establishes communications with our cloud infrastructure it will progressively send the data it has collected (i.e. it doesn't do this all at once).
When a device is in this "catch-up" mode, data will appear delayed in being available in other parts of the system, e.g. via the API.
How long does it take for a device to catch-up?
The amount of time a device takes to fully "catch up" and have all data available via the Wattwatchers system depends on a number of factors, including:
- The amount of time the device was offline, but collecting data (the data "backlog")
- The quality of the communications connection with Wattwatchers' infrastructure
- Other infrastructure performance impacts
If a device reconnects to our infrastructure with a solid connection, it will usually send data at a rate of 1 hour of data every minute.
Thus, if a device has been offline for a day, and collecting data for the entire day, it will usually catch up within approximately 24 minutes.
However, this is only a rule of thumb, and it may take significantly longer, depending on conditions and context.
Does the device send newer energy data before it catches up?
No. The Long Energy protocol is designed to ensure that energy data is uploaded to our servers FIFO (i.e. older entries are sent first) so you can count on the latest Long Energy entries being provided in chronological order.