Strange availability test pattern

[finestructure]

Our availability test in Azure is showing a strange pattern

The higher (slower) band seems new. In the past we only had the lower band in 100-200ms range.

Looking through the last week, there's a test that took 15s - from Central US 🤔

I don't believe I've seen this behave like this before.

[finestructure]

Just to clarify, the 15s test might be an outlier that's not unusual. I routinely check the test and I don't recall seeing this before but that's anecdotal. It may well have happened before but when I check, it's typically the last 24h range and unless an outlier falls in that range it's easy to miss.

What's definitely new is the two different timings. These tests used to have a normal range of up to 100ms. Now that's the fastest they run with ~half of the tests running much slower (> 500ms, up to 1-1.5s). I've not seen that before.