Engineering: SLIs/SLOs
This course separates service level indicators, objectives and agreements, and explains what each one is for. It covers choosing an indicator as a ratio of good events to valid events, turning an objective into an error budget, and alerting on burn rate instead of raw errors. It also asks what objectives were built to solve and how much of that applies to a solo project. It ends with a sentence describing what working means and a challenge implementing error budget arithmetic.
What you'll learn
- ✓The difference between an indicator, an objective and an agreement
- ✓How to choose an indicator and which requests to exclude
- ✓How an objective becomes an error budget that can be spent
- ✓Why burn rate works better for alerting than error counts
- ✓What transfers from objectives to a project with one person
- ✓Implementing error budget and burn rate arithmetic in code
Indicator, objective, agreement
Three terms get used interchangeably, and they mean different things. Separating them isn't pedantry: each one has a different author, a different consequence and a different reason to exist.
Read the full lesson free →Curriculum
7 lessonsIndicator, objective, agreement
Defines indicators, objectives and agreements, and why the objective should be tighter than any agreement.
Choosing an indicator
Shows how to pick an indicator that tracks user experience, shaped as good events over valid events.
The error budget
Explains how an objective inverts into a budget that pays for deploys, experiments and migrations.
Alerting on burn rate
Covers why error-based alerts fail and how fast and slow burn rates map to pages and tickets.
What an objective is for
Describes the team conflict objectives were built to settle and what remains useful for one person.
What to write down today
Proposes writing a sentence about what working means, then measuring before choosing any percentage target.
Putting it together
Summarizes the course, draws two lasting ideas from it and sets a challenge implementing error budget arithmetic.