How to define the status between now and a last checkpoint?

Question

I have sets of probing data from an internal monitoring tool which represent the availability of different services (databases, webservices and so on).

Now my task is to visualize this data and I reached a point where I should make a decision concerning the data interpretation for the most recent data set.

Quick overall definition, each data set reflects the given status at the time when it was verified and the probing intervals vary from service to service, so there is no constant time window. Hence if there is an interval of e.g. five minutes between set A and B, for these five minutes (assuming with B there is a change) the status of A is always assumed.

So far no problem, my question now however is what should be assumed for the time between now and the most recent data.

I see two solutions

• Only visualize data up until the most recent check, and ignore the passed time since then

or

• Assume the status from the most recent check is still valid up until now (like between two given data entries)

I could see arguments for both and hope someone can point me in the right direction as to which approach would be the most logical one.

Answer 1

A simple approach you can do is to show the last returned value and what time the value was returned. A lot of websites which check the status of major websites return it like that as shown below

An implementation might look like this :

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A approach you can use to show the historial data is by showing a graph which shows the status over a period of time like how downrightnow shows it

Answer 2

If you are displaying this data in a chart that represents a continuous flow of time than you can certainly include pixels for representing non-reported status time. A gray area that assumes the most recent reading continues would work.

It might be more accurate to treat this as a list of events. That way there is no abiguity, it's simply a list of records chronologically sorted. The most recent event is listed with a timestamp, and a calculation of minutes or seconds ago.