Only 0.0 - 1.0 objectives?

[mccartney]

target: numeric [0.0, 1.0) # budget target for given objective of the SLO

timeSliceTarget: numeric (0.0, 1.0] # required only when budgetingMethod is set to TimeSlices

This assumes the values will be only between 0% and 100% which seems to match the typical availability service level indicators. And generally a good practice. Although I saw other kind of SLIs in real-life.

Relevant SRE book chapter:
https://sre.google/workbook/implementing-slos/
which generally advocates for defining the 0%-100% ones. And even introduce the notions of "SLI specification" and "SLI implementations" with only the latter ones matching 0%-100%.

TLDR: I suggest to open up for other kind of SLIs, not only the [0,1] ones.

[its02003]

Can you give an example of an objective target where the availability would be something outside of 0-100%?

[mccartney]

Can you give an example of an objective target where the availability would be something outside of 0-100%?

Not for availability. I have only ever saw availability being 0-100%.

But I thought this definition of timeSliceTarget is not only for availability SLIs, but other SLIs too. If so, examples of SLIs which are not 0-100% are:

• p95 of HTTP request processing time per second
• number of failed customer transactions per minute

[Maixy]

p95 of HTTP request processing time per second

This should still be a 0-100% target. With TimeSliceTarget you'd be counting up the number of intervals per rolling window where the p95 was < your target divided by the total number of intervals per window.
ex. Minutes where request processing time p95 < 500ms in the last 28d / minutes in the last 28d
This results in a percentage between 0 and 100

number of failed customer transactions per minute

This should presumably include a threshold that's acceptable, ex. 10 failed transactions per minute is 🆗 but beyond that isn't acceptable.
With that threshold, each minute gets evaluated separately, and we get the similar equation to the above example:
Minutes in the last 28d where the number of failed transactions were less than 10 / total minutes in the last 28d