#42 - Hitting Software SLA Targets through SLOs and SLIs

In this first part of a 2-part coverage, Sebastian Vietz and I work out how to meet SLAs through SLOs and SLIs. This episode covers Chapter 4 of the Site Reliability Engineering book (2016).

Here are 7 takeaways from the show:

1. Involve Technical Stakeholders Early: Ensure that technical stakeholders, such as SREs, are involved in discussions about SLAs and SLOs from the beginning. Their expertise can help ensure that objectives are feasible and aligned with the technical capabilities of the service.

2. Differentiate Between SLAs and SLOs: Understand the distinction between SLAs, which are legal contracts, and SLOs, which are based on customer expectations. Avoid using SLAs as a substitute for meaningful service level objectives.

3. Prioritize Meaningful Metrics: Focus on a select few service level indicators (SLIs) that truly reflect what users want from the system. Avoid the temptation to monitor everything and instead choose indicators that provide valuable insights into service performance.

4. Align with Customer Expectations: Start by understanding and prioritizing the expectations of your customers. Use their feedback to define service level objectives (SLOs) that align with their needs and preferences.

5. Avoid Alert Fatigue: Be mindful of the number of metrics being monitored and the associated alerts. Too many indicators can lead to alert fatigue and make it difficult to prioritize and respond to issues effectively. Focus on a few key indicators that matter most.

6. Start Top-Down with SLIs: Take a top-down approach to defining SLIs, starting with customer expectations and working downwards. This ensures that the selected metrics are meaningful and relevant to users' needs.

7. Prepare for Deep Dives: Anticipate the need for deeper exploration of specific topics, such as SLOs, and allocate time and resources to thoroughly understand and implement them in your work.