The purpose of any CI/CD pipeline is to enable DevOps teams to deliver software quickly and continuously. But “quickly” is a relative term. Some DevOps pipelines are faster than others. The choices that DevOps teams make about how to structure their pipelines and optimize processes within them exert a major impact on the speed of CI/CD operations.
How can your team make its CI/CD pipelines as fast as possible? Keep reading for actionable tips on optimizing DevOps pipelines for speed.
What is a fast CI/CD pipeline?
Before diving into tips about speeding up CI/CD, let’s briefly explain what a fast CI/CD pipeline looks like.
Put simply, a speedy CI/CD pipeline is one that allows teams to release applications as rapidly as possible. It does this primarily by speeding up the individual processes that make up CI/CD pipelines. It also prevents issues that could cause release delays — or, worse, that could result in an application release being rolled back.
Note, too, that CI/CD speed is not based solely on how rapidly CI/CD processes execute. It’s also a measure of throughput across the pipeline, meaning how many processes can run at the same time. The more you can do in parallel, the faster your CI/CD pipeline will be.
How to speed up CI/CD
Here are five ways that DevOps teams can achieve those goals by making individual CI/CD processes as quick as possible and mitigating the risk of delays or bottlenecks within the pipeline.
1. Use CI/CD branching
Another way to mitigate the risk of delays due to feature changes in some cases is to employ CI/CD branching. Under a branching model, teams implement and test each major feature change (or set of related changes) within a separate “development” branch, or version, of the CI/CD pipeline. At the same time, they maintain a stable “master” branch. After a change has been vetted within a development branch, it is integrated into the master branch.
The advantage of branching is that if changes cause problems, they are isolated within a development branch of the pipeline. CI/CD operations can continue uninterrupted within the master branch (as well as other development branches) while developers work through the problem. In this way, branching helps DevOps teams manage a large volume of changes while minimizing the risk of disruptions that could slow down CI/CD operations.
There is some debate about the merits of feature branching. Researchers like those at DORA have found that trunk-based CI/CD pipelines can be faster. However, results will vary depending on how many developers you have on your team and how many features you are managing. CI/CD branching is arguably more effective for small to mid-sized development teams, and in cases that involve large volumes of feature changes.
2. Employ canary releases
Canary release patterns are another useful technique for speeding up CI/CD. In a canary release pattern, DevOps teams release a new version of an application to a subset of end-users before pushing it out to the entire user base.
From the perspective of CI/CD operations, canary releases offer two major benefits. First, they allow teams to roll back problematic releases more quickly. Because a bad canary release will only be deployed to a fraction of your total users, you can replace it with a stable release faster than you could if you had deployed a buggy application to your entire user base.
Second, to a degree, canary releases can reduce the amount of pre-deployment application testing that teams need to perform, which in turn allows applications to be released faster. Although canary releases are certainly not a substitute for pre-deployment testing, they make it possible to vet application changes among a subset of end-users in production in a relatively low-risk way. In this sense, canary releases allow teams to gain confidence in a new application release even if they did not perform exhaustive pre-deployment tests on it.
3. Avoid making too many feature changes at once
One common source of CI/CD bottlenecks is release cycles in which developers attempt to implement too many application changes in a single release.
When you do this, you increase the risk that a change will trigger a problem (such as a failed test) that causes the release to be delayed. In addition, the more features you implement at once, the harder it is to determine which change was the root cause of a problem. The time developers spend tracking down the commit that resulted in a failed test can slow down CI/CD operations even more.
Being able to run builds in parallel can mitigate these risks by allowing builds to continue executing in the event that one build fails due to problems with a particular feature. However, it’s still a best practice to refrain from cramming too much change into each release. It’s better to deploy more releases that contain fewer changes each than it is to have fewer releases that introduce more changes per release.
4. Use containers
Among the many benefits of containers is a simpler and faster CI/CD pipeline.
The main reason why is that, when you containerize your application, it becomes much easier to achieve environment parity, which means a software environment that is the same at all stages of the pipeline. In other words, if your application runs in a container, you can test it and run it in the same container-based environment. Variables in configuration between dev/test and production environments, or (if you deploy to multiple locations) between different production environments, don’t matter as much because containers abstract applications from the host environment.
5. Cache and reuse artifacts
In many cases, artifacts from previous CI/CD release cycles can be reused during new cycles. For instance, a package or container image that your application depends on can be used for subsequent application tests.
To avoid having to download or rebuild artifacts completely for each cycle, you should cache artifacts and reuse them where possible using artifact repositories like Artifactory.
By reusing artifacts that you already have on hand, you can significantly speed overall CI/CD operations. At the same time, you can reduce the risk that a problem in building a software resource delays a release cycle.