Successful software development demands the delivery of fast, scalable systems to ensure high performance and adaptability to meet evolving needs. Today's users expect seamless experiences, lightning-fast responses, and applications that scale effortlessly. In the quest to meet these high standards, however, even the best-designed systems can accumulate a hidden adversary known as "performance debt," which negatively impacts a system's speed and efficiency.
Performance debt directly puts a system's success at risk. Instead of a high-performing system that delivers on user expectations, developers create a system that fails to meet production goals in critical areas such as efficiency, scalability, and responsiveness. For these reasons, it is crucial for product owners to gain an in-depth understanding of performance debt, the best strategies to reduce it, and when to implement the strategies for maximum effectiveness.
What Is Performance Debt?
The terms "technical debt" and "performance debt" may sound similar, but there are important differences between the two. Technical debt, a term created by developer Ward Cunningham, one of the 17 authors of the Agile Manifesto, refers to a system's broader maintainability and scalability and its overall code health. Performance debt, on the other hand, refers specifically to the negative impact certain decisions made during the development process have on a system's speed, scalability, and efficiency.
When a developer decides to take a shortcut or institute a "quick fix" without considering the long-term ramifications of that decision, it can potentially lead to performance debt. In other words, a system falls short of being all it could be because compromises were made along the way. In addition to shortcuts and quick fixes, other frequent causes of performance debt include selecting outdated technology, scalability/capacity oversight, a lack of expertise, inadequate documentation, changing requirements, deferred maintenance, poorly defined upgrades, poor tool or hardware implementation, and shortsighted performance goals, which frequently lead to inefficiencies that were never even considered.
The biggest cause of performance debt is inadequate performance testing. Typically, this situation arises when the window for performance testing/engineering is compressed due to an unforeseen delay in product development. That delay often causes a reduction in testing scope, which leads to fewer inefficiencies being identified and the accumulation of higher-performance debt. Developers then end up with a system that falls far short of what it could have achieved in speed and efficiency, a significant risk in today's marketplace, as speed and efficiency are typically valued by software users. Accumulating performance debt can result in several negative effects, including:
- Unhappy customers. Slow load times, inadequate security, and frequent system crashes can lead to poor user experiences.
- Missed deadlines. Developers who have to go back and address code issues can slow production.
- Poor reviews. Speed and efficiency issues can lead to negative word of mouth and ratings about the system, damaging a company's reputation.
- Low morale. In software development, few things can wreck team morale more than dealing with consistently bad code.
How to Reduce Performance Debt by Testing Early
There are tools and frameworks in the performance engineering space that can help reduce performance debt. The best strategy for reducing performance debt is to test early and continuously. Integrate performance testing tools directly into the CI/CD pipeline. Almost all major load testing tools (JMeter, LoadRunner, Gatling, etc.) have a framework to integrate into the CI/CD process.
For mission-critical applications, performance testing and application benchmarks can be performed even earlier using frameworks like JMH (Java Microbenchmark Harness) for Java and BenchmarkDotNet for .NET applications. To ensure a best-use scenario, this testing needs to be expertly planned and executed. Successful implementation of these tools and frameworks into the CI/CD pipeline ensures that performance tests are run automatically every time changes are made, enabling early detection of performance issues.
The importance of continuous testing can't be overemphasized. First, the cost of identifying and correcting software defects increases exponentially with time. Second, it is easier to fix bugs while developers are still creating code and it is fresh in their minds rather than after the work on the software has finished and it has been released to the public. In a recent survey conducted by Sourcery, respondents with high levels of debt reported spending nearly 50% more time on bug fixing and understanding existing code than respondents with low-performance debt. This discrepancy then resulted in respondents with high-performance debt spending 40% less time working on developing new features for their software. Statistics like these make it easy to see how accumulating performance debt can put companies at a distinct disadvantage in the marketplace.
To save time and money, it is imperative for companies to institute and remain committed to frequent testing throughout the development process. Introduce continuous performance testing into the development lifecycle as early as possible to identify defects while the code is written or is in the code review stage. Adopting this Agile approach to testing reduces risks and costs. It also allows developers to follow a continuous integration scheme where performance testing is elevated to performance engineering, a more comprehensive approach to optimization. Instead of simply conducting load tests at the end of a development phase, with continuous performance engineering, there is constant feedback regarding speed, efficiency, and defects throughout the development process.
Additional Strategies to Reduce Performance Debt
Once a robust performance testing process has been integrated into the software development process, take these steps to further reduce performance debt:
- Plan ahead. Clearly define performance goals and ensure the architecture is scalable and meets required capacity parameters. Also, emphasize selecting the right technologies, data structures, and algorithms before development begins. If there are new technologies/frameworks introduced in the architecture, ensure valid POCs are conducted to ensure performance goals are met.
- Focus on code quality. Strive to write clean and efficient code using the right design patterns for the problem and institute a regular code review process. Create a best practices document with performance patterns to use and anti-patterns to avoid.
- Refactor code. Periodically refactor code to improve code quality and efficiency and ensure it can be adapted to new requirements. Also, keep the technology stack updated to take advantage of performance improvements in newer versions.
- Monitor diligently. Invest in the right observability tools for critical stages of development. Define key performance indicators (KPIs) and ensure they are monitored, collected, and reported. Any anomalies should be investigated and fixed right away.
Start Testing Early
A "build now, fix later" philosophy has thrived in software development, but in today's tech-savvy marketplace, that philosophy can quickly put a company at a disadvantage. What Ward Cunningham once said about technical debt can also be applied to performance debt: "Shipping first-time code is like going into debt. A little debt speeds development so long as it is paid back promptly with a rewrite. The danger occurs when the debt is not repaid. Every minute spent on not-quite-right code counts as interest on that debt. Entire engineering organizations can be brought to a stand-still under the debt load."
It is vital that developers introduce and integrate testing as early in the development process as possible. It's also important to remember that managing performance debt is not a one-time activity but a continuous cycle that encompasses frequent testing, strategic planning, proper system design, and constant monitoring throughout the software development process.
About the Author:
Hariprabu Sengoden Kandasamy is a principal architect with more than 20 years of experience in cloud optimization, software performance engineering, and tools development. Hariprabu has lent his expertise to numerous Fortune 500 companies, driving system optimization projects that have consistently enhanced the performance and efficiency of complex systems and technologies. He received his bachelor's degree in mechanical engineering from Bharathiyar University, India. For more information, contact [email protected].