Service Level Objectives (SLOs) and Error Budget Policy

In our efforts to balance feature development with system reliability, I need to establish clear Service Level Objectives (SLOs) and an error budget policy. I need your help to define and document this policy for our key services: User Authentication Service (authentication and authorization) and the Product Catalog Service (product information retrieval). The current availability for both services is around 99.5%, with average latency of 300ms for authentication and 400ms for product retrieval. We currently use Prometheus for monitoring but lack comprehensive dashboards tailored for SLO compliance.

Could you help by:

• Defining measurable SLOs for the User Authentication Service and Product Catalog Service, including specific availability targets (e.g., 99.9% availability) and latency targets (e.g., 200ms latency for User Authentication, 300ms latency for Product Catalog).

• Creating an error budget framework that outlines acceptable risk levels. This should address potential risks such as database outages, code deployments causing performance degradation, and spikes in user traffic. The framework should define triggers for corrective actions (e.g., halting deployments, increasing resource allocation) when the error budget is being consumed too quickly.

• Suggesting monitoring tools and dashboards to track SLO compliance in real-time. This should integrate with our existing Prometheus setup and provide clear visualizations of SLO adherence and error budget consumption. Include specific queries or dashboard configurations that would be useful.

Provide the output as a policy document targeted at engineers and managers. The document should have the following structure:

• Title

• Table of Contents

• Introduction (Purpose and Scope)

• Service Level Objectives (SLOs) – detailed for each service

• Error Budget Policy – framework and triggers

• Monitoring and Alerting – integration with Prometheus

• Incident Response – how to react when SLOs are breached

• Review and Improvement – policy review cycle

• Include practical examples and implementation guidelines. For the monitoring section, provide example Prometheus queries and dashboard configurations. For the incident response section, outline a sample escalation process.

• Clarify the desired level of detail for the implementation guidelines, including example commands and configuration snippets where appropriate.