The Ultimate Guide to SLI

The Ultimate Guide to SLI

The Site Reliability Engineering strategy includes Service Level Indicators (SLI). It would be impossible to manage IT services correctly without knowing how SLI and related processes work. Measuring services can give businesses a better understanding of their services. Measurement and evaluation of service behavior are called SLI. A metric’s value and basic properties are defined.

Choosing the right metrics allows businesses to find and take the right action when something goes wrong and creates a huge issue. This blog explains the framework of service level indicators.

What is SLI?

SLI is the quantitative measurement of the level of service. The key use of SLI is to measure request latency. Other than that, businesses can use SLI to measure error rate (fraction of request received), system throughput (request per second). Engineers use aggregated information like raw data. Then they turned it into a percentage, average, or a rate.

Another indicator is availability. Availability is a fraction of the time. This time tells when the service is usable. The fractions are also called yield. Users can also measure durability. Though 100% availability is impossible in the actual world situation, the nearer the rate is, the better. These percentages indicate the availability of the values.  

One of the advantages of SLI is users can directly measure and observe the level. It also represents the user’s experience. In short, it defines what exactly users are going to measure.

Best Practices of SLI

Following are best practices of SLI that users can follow to get accurate information:

1.      First, members need to understand the users and their needs. To enhance users’ experience, they should be able to get access without delay. Organizations need to ensure availability, latency, and throughput. Engineers can add facial features or fingerprint systems on the site.

2.      Make the SLI directly observable and measurable by the users. Using metrics like CPU utilization or desk latency is not suitable. Users cannot directly use these tools to measure. Users need, and behavior plays a crucial role here.

3.      Data and information are an inseparable part of SLI. Developers need to choose data and information to get accurate results carefully. So, error-free data is a must.

4.      To keep data, the SLI system needs a sufficient amount of storage. Data loss is a critical issue. So focusing on availability, latency, and durability of storage systems is also a part of SLI.

5.      As SLI and SLO evolve, it’s good to measure SLI from time to time to cope with the changes.

The process of getting a mature set of service levels may take some time. However, all complex works can be in vain if they are not carried out in accordance with best practices. Engineers can make more informed decisions when they have an accurate SLI.