Software reliability can be defined as the probability of a failure-free operation of a computer system over a specified period, under a set of specific conditions. It is an important factor in determining software quality.
Site reliability engineering (SRE) is a software approach to IT operations that helps organizations to improve the reliability of their systems.
The Importance of Improving Reliability
Reliability is one of the key attributes of software quality.
No matter how many exciting features you have built into your system, it is unlikely that you will manage to retain any users if your system is unreliable.
Over the years, software has become increasingly complex. Each system has more parts to it, which means that there is more potential for things to go wrong. This has made it more important than ever for organizations to prioritize reliability.
10 Ways You Can Improve Reliability
1. Understand customer pain points
Understanding the pain points of your customers is vital when determining the level of reliability your service will require. You will need to fully consider the impact that performance issues will have on your users. You can never have a completely perfect service, so you will need to determine which parts need to be prioritized.
For instance, occasional downtime of your service might have less of an impact on your users than a three-second delay every time they try to log in. A mere one-second delay in a page’s loading speed leads to an 11% drop in page views.
2. Create SLOs for reliability
Service-level objectives (SLOs) have quickly become a fundamental part of reliability.
They outline a set of objectives that a team must meet to fulfill the agreement that an organization has made with its clients or users. An example of an SLO is “99% availability within a 30-day window”.
When it comes to setting SLOs, the goal is to find the sweet spot where customers are happy with a set level of reliability, and it is reasonable to maintain.
Increasing reliability past the point where customers are satisfied with it can waste time and resources that could be better spent improving other areas of the organization.
3. Hire SREs
In 2021, the Bureau of Labor Statistics (BLS) reported that job growth for site reliability engineers is projected to increase by 21% by 2028. This is significantly higher than many other roles – and for good reason: SREs are a vital part of many organizations.
SREs are designed to bridge the gap between development and operations teams. Their role is to automate processes, such as analyzing logs and testing production environments, to enhance the efficiency, performance, and monitoring of processes in software development.
This frees up time for developers to focus on developing new features and bringing them to production, and for operations teams to focus on addressing important incidents that require their time, instead of spending their time solving recurring issues.
4. Build resilient systems
You should consider reliability as your system’s most important feature.
Developers can use SLOs and error budgets – essentially the number of errors that your system can accumulate within a given period before your users become unhappy with your service – to help them build resilient systems that are built for reliability.
There are also several additional reliability practices you can adopt, such as having contingencies for using backup servers, and error correction algorithms for incoming network data.
5. Create a culture of reliability
A culture of reliability involves each member of an organization individually working towards an overall shared goal of maximizing the availability of people, services, and processes within the organization, and consistently making decisions that support this.
Teams should work together to create a vision of what is possible, and then map out the steps that they must follow to achieve their desired goal.
They should consistently set and review expectations – especially for key individuals within the organization – and provide support and encouragement throughout the process.
6. Have user-focused metrics
The main purpose of reliability is to improve the level of service that your organization can provide to its users. Therefore, it makes sense to focus your metrics on these users.
Service-level agreements (SLAs) are used to outline the expectations between the service provider and the customer. Failed SLAs can be expensive, so teams should keep a close eye on these metrics to make sure that they are not at risk of being missed.
7. Invest in reliability tools
Selecting robust reliability tools and using them in the right context is vital when it comes to improving the reliability of a service.
For instance, DataDog is a tool for application performance monitoring (APM), Slack is a tool for real-time communication, and PagerDuty can be used to help teams with automated incident response.
Reliably’s platform can also be used to help teams to create objectives, aggregate a system’s reliability score, and set smart alerts. This can help to drive organizations through their objectives.
8. Monitor and log
Previous incidents can provide your team with invaluable information about how your system functions. As a result, monitoring and logging incidents that occur can help you to solve future incidents much more efficiently.
Keeping a consistent log also means you’re less likely to be left completely stuck if someone leaves your organization, because the rest of your team will be able to read the notes they left and learn how to fix issues themselves instead of having to start from scratch.
9. Try chaos experiments
Chaos experiments, also known as chaos engineering, involve intentionally introducing failures into a production system to prepare for a potentially stressful future hypothetical scenario. Examples of such scenarios include server outages, failed third-party integrations, or high network loads.
This is a key part of improving system reliability because it lets teams test out the effectiveness of their response to a potential issue, without the potential repercussions of a real issue.
This way, teams can learn from their mistakes and improve their response in preparation for a real incident.
10. Learn from incidents
No matter how much you try to prevent it, unforeseen incidents will arise. Perhaps the most obvious way – and yet, often the most difficult – to improve the reliability of your systems and services is to learn from previous incidents.
To do this, you should classify your incidents based on their severity and type. The classification of your incident should determine who is alerted of the incident, and how they should respond. Finally, you should record the specific details of the incident.