What are Service Level Objectives (SLO)
SLOs are important pieces that are used to define Service Level Agreements (SLAs). As described by Wikipedia, “SLOs are specific measurable characteristics of the SLA such as availability, throughput, frequency, response time, or quality. These SLOs together are meant to define the expected service between the provider and the customer and vary depending on the service’s urgency, resources, and budget.”
Google breaks down the components of SLAs and SLOs further in the Site Reliability Handbook. Understanding the terminology and how each part fits together is a vital component in creating an SLO methodology that works for your business.
Service Level Terminology
Indicators: A service level indicator (SLI) is the defined quantitative measure of one characteristic of the level of service that is provided to a customer. Common examples of such indicators are error rate or response latency of a service.
Objectives: A service level objective (SLO) defines the target value for the service level that is measured by a service level indicator. As an example, the SLO could specify that a given SLI is 99.9% of the time fulfilled.
Error Budget: The specified target value of an SLO implicitly defines a small budget where the service is allowed to not work fully reliably. This error budget allows for the planned or unplanned downtime of the service that is unavoidable in practice.
Why Implement SLO Methodology?
Instana has done extensive research on Service Level Objective methodology among our customer base to better understand how they are being used in practice. We have learned that Service Level Objectives as a methodology are gaining a lot of adherence. As such, many organizations are looking for tools and advice on how to best implement their SLO methodology.
When done properly, Service Level Objectives promise to enable teams to make better decision making and prioritization around reliability and feature development. Having an SLO methodology in place improves communication across the board by making those conversations more factual and less emotional when it comes to the impact of incidents. And, they even help make better business decisions based on current Service Level Indicators. Last but not least they help improve overall organizational monitoring maturity.
Managing SLOs and SLIs in Instana
Modeling User-Journeys
A common pitfall in defining SLOs is defining them too granular instead of simplifying them by customer experience. When SLOs are too granular or in-depth they often fail to fulfill the promises and benefits of SLO methodology as outlined above. Instana, through the use of the Application Perspectives Creation Wizard, allows for Service Level Objectives to be defined by customer experience through the use of user journeys. The Application Perspectives Creation Wizard enables the creation of specified user journeys with easy selection and specifications via ‘blueprints’. With the creation wizard the user journey specification is interactive, as items are specified the user can see what data is expected to be returned.
Configuration of SLIs
Once the critical user journeys have been identified, they need to be ordered by business impact and service owners need to determine the metrics to use as key indicators. Instana makes it easy to define, validate, and visualize meaningful SLIs and SLOs, derive error budgets, and enable immediate root-cause analysis of service level violations.
Setting up SLOs
With Service Level Indicators created based on user journeys, the creation of SLOs is simply a matter of pulling the right SLIs into the SLO you are creating. Instana utilizes our Custom Dashboarding capabilities to create widgets for your SLOs. The SLO widget can show information for either time-based or event-based SLI configurations.
Instana’s implementation of SLI, Error Budget, and SLO has been designed to be compliant with the Google Site Reliability Workbook definition of SLO methodology, as it is currently a widely acknowledged best practice. These best practices are then enhanced by combining the SLO and SLI capabilities with Application Perspectives user journeys and by tightly integrating SLI, SLO, and Error Budgets with Custom Dashboards. This allows for easier sharing and closer collaboration with non-engineering roles, such as Product Managers and business stakeholders. This is key to fully realizing the benefits for a successful SLO methodology implementation.
Instana’s SLI and SLO methodology is also tightly integrated with Unbounded Analytics, making it easy to quickly uncover the root cause of any availability or performance issue that leads to the depletion of error budgets or violations of SLOs.
Get Started with SLOs in Instana Today
If you want to experience the full power of Instana’s SLO methodology you can sign up for a free trial of Instana and see for yourself.