Question about SLO

[Romanenkov_Al3x]

Hi Team,

I have a question for you guys if you could share to me knowledge how exactly SLO calculates in case if we have several services in one SLO. From my practice, I always choose only one service to avoid any problem, but in this case a question from colleagues who want choose several.

For example - Evaluating period -1h and I have three services and want Service-level availability SLO for them:

Service A ( 1 failed requests / 100 request/h ) SLO for A - 99%

Service B ( 0 failed requests / 1 request/h ) SLO for B - 100%

Service C ( 500 failed requests / 1 000 requests/h ) SLO for C - 50%

Service A,B,C (management zone filter) I have SLO for ABC -  some_percentage 

For example - 80.363%. I can see it in wizard at Evaluate step.

How exactly calculation takes place?

From real tests I have two services with 100%, and 90%, and I can see that SLO for management zone for these two services not just (100 + 90)/2 = 95% 😃

I would appreciate any help with this 🙂

Regards,

Alex Romanenkov 

[michiel_otten]

Hi Alex,

Isnt it basically: all the requests compared to all the succeeded requests?

So if you have 100% and 95% for each service,  it can be different. Since it can happen that the 95 procent service has more requests in total? 

SLO example could be:

• Number of successful HTTP requests / total HTTP requests (success rate)

If you use 2 services, the requests of both are combined to do the calculation. You can replay it by just fetching the metrics in data explorer en do the calculation yourself 🙂 

KR.

Michiel