The past and present of the underlying development principles of PHP7: major improvements from PHP3 to PHP7

The past and present life of the underlying development principles of PHP7: major improvements from PHP3 to PHP7

Introduction

With the rapid development of the Internet, PHP has become One of the most commonly used programming languages ​​in web development. As a language that is easy to learn and use, PHP has wide applications in web application development. With the continuous iteration of versions, PHP7 has become the latest version, bringing many major improvements and optimizations. This article will explore the past and present of the underlying development principles of PHP7, and introduce the major improvements from PHP3 to PHP7.

1. The underlying development principles of the PHP3 era

PHP3 was released in 1998 and is the first official version of PHP development. In this version, PHP adopts the underlying development principles based on the interpreter. Simply put, an interpreter is a tool that parses and runs line by line source code. PHP3 adopts the simplest interpreter model, which requires reading and parsing the entire script file each time and then converting it into executable machine code. Due to the characteristics of interpreted execution, PHP3 faces great challenges in performance and has low operating efficiency.

2. The underlying development principles of the PHP4 era

In order to improve performance, PHP4 introduced the Zend engine, which is a basic interpretation engine. Zend Engine has made significant improvements to PHP4, compiling PHP code into Zend opcodes and using Zend Engine to execute these opcodes. This improvement greatly improved the performance of PHP4, but there are still some problems. Due to the design limitations of the Zend engine, PHP4 cannot support multi-threading, which is a big problem in high-concurrency web applications.

3. The underlying development principles of the PHP5 era

PHP5 has made greater breakthroughs in the underlying development principles. PHP5 introduces Zend Engine II, which is a completely new engine that is completely different from the Zend engine in PHP4. Zend Engine II adopts a thread-based model and supports multi-threaded processing. It also improves the way memory is managed and error handled, providing better performance and reliability. In addition, PHP5 also introduces the concept of extensibility, allowing developers to increase the functionality and performance of PHP by writing extensions.

4. The underlying development principles of the PHP7 era

PHP7 is the latest version of PHP, released in 2015. PHP7 introduces Zend Engine III, a major improvement designed to improve PHP performance. By using JIT (just-in-time compilation) technology, Zend Engine III compiles PHP code into local machine code, greatly improving execution speed. In addition, PHP7 also optimizes memory management and introduces some new language features, such as strong type declarations and scalar type declarations.

Summary

Through a review of the underlying development principles of PHP, we can clearly see the major improvements in PHP from PHP3 to PHP7. From the initial interpreter-based model to the current JIT technology-based model, PHP has made huge breakthroughs in performance and functionality. The release of PHP7 marks a new era of PHP's underlying development principles, providing more efficient and reliable solutions for Web application development. As technology continues to advance, we look forward to the future development of PHP to meet the needs of more complex and high-performance web applications.

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