22 Final Words- Practice to Gain Real Knowledge #

Hello, welcome to the last part of this column. Up to this point, we have covered all the topics. During the learning process, you will find that the ideas in this column are very clear. It includes many methodologies for performance optimization and frequently asked interview questions, which are worth studying and pondering repeatedly.

However, the writing process was not so smooth. As I said in the beginning, “Performance optimization is a systematic engineering, which requires extensive and in-depth technical skills from engineers.” Therefore, explaining the knowledge points of “performance optimization” that require both solid foundations and practical experience is a big challenge.

During the writing process, I also referred to dozens of books on performance optimization, but I did not find the explanation I wanted. Many books are targeted at beginners, and they only provide simple introductions to the knowledge points without relating to the practical theme of performance optimization. This is the case in most ordinary Java basic books. Even the authoritative book “Java Performance Optimization Guide” spends a considerable amount of space explaining the JVM and many theoretical knowledge points that cannot be truly practiced in work.

Previously, I also created a column called “In-depth Java Virtual Machine” on Lagou Education. I spent a total of 25 lessons explaining the JVM, but in the section on performance optimization, I compressed it into 3 lessons, so many details could not be expanded upon.

Given the above two situations, the above approaches cannot comprehensively and completely explain “performance optimization”. Therefore, I decided to create a new column titled “Performance Optimization in Action: 21 Lessons”, selecting the most commonly used components in work to explain them in conjunction with theoretical performance optimization points.

Throughout the course, I have emphasized the systematic and complete nature of thinking. In performance optimization, you should not only focus on performance optimization itself, but also pay attention to the problems it introduces. Performance optimization is not about “coincidentally” knowing how to optimize a certain point, but requires a lot of preparation work and data support. You can refer to the mind map of “Lesson 21: The Process and Methods of Performance Optimization”, which will help you systematically analyze performance bottlenecks, select the right optimization methods, and handle the side effects of optimization.

You will find that many legacy systems do not meet the requirements for applying certain performance optimization principles. Before optimizing, you need to refactor your code. So, you might as well be demanding of your code. Analyze if there is any room for optimization for any request that takes longer than 1 second, and grasp every opportunity to practice. I believe that after multiple practices, you will have a deeper understanding of performance optimization.

Although this column is coming to an end, it does not mean that your learning of performance optimization should stop here. This column is just the beginning, and you need to practice on your own to appreciate the scenery inside. Especially for the theme of “performance optimization” which is inherently practical, in your daily work, I hope you will continue to broaden your cognitive scope and deepen your technical strength. I believe that you will make a qualitative leap.