Growth bottlenecks faced by PHP engineers_PHP Tutorial-PHP Tutorial-php.cn

As one of the most widely used languages in Web development, PHP has a large number of fans. So are you an excellent programmer? While practicing self-cultivation, have you ever thought about facing various Various problems, how should I break through my own bottlenecks so that I can develop better?

PHP engineers face growth bottlenecks

First of all, make it clear that the PHP engineer referred to here refers to the person who mainly uses PHP to develop Web systems and has not worked in other languages. I have about 3 to 4 years of work experience. I am basically comfortable in developing ordinary Web systems (millions of accesses, less than 1,000-level data, or the business logic is not particularly complex) without any problems. But they will point like this:

　◆Do not use other languages except PHP, you may click on shell scripts.

　◆Not good at mastering PHP (have not read many PHP manuals, except libraries).

　◆The knowledge base is relatively narrow (faced with the demand, apart from using PHP and mysql, I don’t know other solutions).

　◆PHP code is mainly process-oriented, and I think the object-oriented implementation is too convoluted and difficult to understand.

These PHPers lack ideas when they encounter projects that require high performance, high concurrency processing, and large amounts of data, or the business logic is relatively complex (the system needs to solve business problems in multiple fields). They are unable to analyze the essence of the problem and have poor technical judgment. They can quickly find temporary solutions to the problem, but often the system and themselves collapse step by step in the constant temporary solutions. So how do you improve yourself? How can you challenge a more difficult system?

Where are the higher challenges?

Combining my own experience, I list some specific challenges to give everyone a perceptual understanding.

What are the challenges of high-performance systems?

　◆How to choose a web server? Should you use fast-cgi mode;

　◆Should you use a reverse proxy service? Choose full memory cache or hard disk cache?

　◆Is load balancing required? Is it based on the application layer or the network layer? How to ensure high reliability?

　◆How is the performance of your PHP code? How about after using optimization tools? Where is the performance bottleneck? Do you need to write an extension in C?

　◆What are the characteristics of user access? Is it more reading or writing? Is it necessary to separate reading and writing?

　◆How is data stored? What is the writing speed and reading speed? How does the access speed change as data increases?

　◆How to use cache? How to consider failure? How to ensure data consistency?

What are the challenges of high-complexity systems?

　◆Can you identify the fields corresponding to the business? Is it one or multiple?

　◆Can the business be reasonably abstracted, so that changes in business rules can be realized at a small cost?

　◆Can the consistency and security of data be guaranteed?

　◆Whether you have mastered object-oriented analysis and design methods

If you can answer the questions listed here in the affirmative, it means that you are technically ready to become an architect. If you can't answer it yet, you need to strengthen in the following directions.

How to improve and break through bottlenecks

If you still can’t answer, you need to strengthen in the following directions:

　◆Analyze the principles and operating mechanisms behind the technology you use, which can improve your technical judgment and improve the correctness of your technical solution selection;

　◆Learn important knowledge during college, operating system principles, data structures and algorithms. Know that you used to study for exams, but now you need to study for yourself and let yourself know why;

　◆Start learning C language again, even though you have already learned it in college. This is not only because you may need to write PHP extensions, but also because, in C applications, there is an environment that always cares about performance, memory control, variable life cycle, data structures and algorithms;

　◆Learn object-oriented analysis and design, which is an effective method to solve complex problems. Learn abstraction, it is the only way to solve complex problems.

How to study effectively is a big problem. "Architecture-centered, use case-driven, iterative development", borrowing this idea, effective learning methods can be expressed as follows: centered on principles, models or mechanisms, task-driven, iterative learning. It's a bit abstract, let's give an example to illustrate how to learn.

Purpose: Learn how to improve processing performance.

Iterable-driven task: Find the location by IP. This is a common task for web applications, and the IP database contains about 100,000 rows of records.

First iteration: Implement functionality without considering performance (implemented through PHP)

Since it is not possible to search the region directly through KEY (IP), simple methods such as directly placing it in the data or through an associative array are not possible. The idea is to sort the data first and then search:

　◆How to search by IP? Binary search is the fastest for sequenced data.

　◆How to sort? Of course you can use the library function sort, but since you are learning, you should implement quick sort yourself.

Learning objectives: Sorting algorithm, search algorithm

PHPer’s data structure and algorithm foundation is relatively poor. I usually don’t have any tasks in this area, and I don’t learn it myself, so I lack knowledge in this area. However, the problems solved by programming will ultimately come down to the data structure and the algorithms that operate on this data structure. If the data structure algorithm is always in your mind, you will be able to clearly understand its inner structure when you encounter a problem, and the solution will naturally emerge.

Second iteration: Optimizing data loading and sorting

If you do the first step, it is basically not available because the data needs to be loaded and sorted every time, which is too time-consuming. The solution is to load and sort the data once and put it in a place where each PHP process can access it. Putting it in Memcache is an easy problem for everyone. In fact, putting it in shared memory (supported by EA and other accelerators) is a faster way, because memcache also has more network operations. Is the data put into shared memory as a whole or in blocks? How to test performance? How to analyze bottlenecks (xdebug)? Driven by these issues, you will learn.

Learning objectives: Methods to detect, locate, and optimize PHP performance; the impact of PHP implementation structure on performance.

The third iteration: Writing PHP extensions

The performance still cannot be improved, and I have to enter the world of C/C++. But from now on, you will not only be a PHPer but also an all-round engineer on the server side. Of course, this will be a huge challenge for students who have never done C/C++.

Learning goals: Learning C/C++, writing PHP extensions

How to determine the mechanisms and principles that need to be learned? How to find the driving learning tasks? I have no idea about what needs to be learned, how can I answer the above two questions? Find out what needs to be learned from the positioning of this technology The key point is how it does it (mechanism) and why it can do it. List the most common applications of this technology as a learning task and practice them from simple to difficult.

If I need to learn JavaScript, I have some perceptual knowledge of HTML and CSS. The first thing to understand is that JavaScript is a dynamic language in the Web field, which mainly solves the dynamic interaction of web pages. The key points to learn are as follows:

　◆How JavaScript interacts with HTML (mechanism)

　◆What are the dynamic characteristics of JavaScript, and how are they different from other dynamic languages? (Language model)

If you are completely self-study, find the key points that need to be learned (mechanism, model, principle) and set learning tasks. It is indeed not that easy to grasp. If you find an experienced person to guide you or add a learning team, the speed of learning will indeed be greatly improved.

Finally, I want to say to everyone: PHP is used because it is simple, but its simplicity cannot limit our growth!