SQL performance optimization PHP performance optimization produces highly optimized code

1. Upgrade PHP to the latest version
The easiest way to improve performance is to continuously upgrade and update the PHP version.
　2. Use an analyzer
　 There are many reasons why a website may run slowly, and web applications are extremely complex and confusing. And one possibility lies in the PHP code itself. This analyzer can help you quickly identify code causing bottlenecks and improve the overall performance of your website.
　Xdebug PHP extension provides powerful functions that can be used for debugging and analyzing code. It is convenient for developers to directly track the execution of scripts and view comprehensive data in real time. This data can also be imported into the visualization tool KCachegrind.
　3. Error detection report
　 PHP supports powerful error detection functions, which facilitates you to check errors in real time, from more important errors to relatively small running prompts. A total of 13 independent report levels are supported, and you can flexibly match these levels to generate user-defined detection reports.
　4. Utilize PHP extensions
　Everyone has always complained that PHP content is too complicated. In recent years, developers have made corresponding efforts to remove some redundant features in the project. Even so, the number of libraries and other extensions available is impressive. Some developers are even starting to consider implementing their own extensions.
　5. Use PHP accelerator
　Under normal circumstances, PHP scripts are compiled and executed by the PHP engine and will be converted into machine language, also called opcodes. If a PHP script is compiled repeatedly and gets the same result, then why not skip the compilation process entirely?
You can achieve this with the PHP accelerator, which caches the compiled machine code of the PHP script, allowing the code to be immediately requested execution without going through the tedious compilation process.
　For PHP developers, there are currently two available caching solutions. One is APC (Alternative PHP Cache, optional PHP cache), which is an open source accelerator that can be installed through PEAR. Another popular solution is Zend Server, which not only provides opcode caching technology, but also provides caching tools for corresponding pages.
　6. Avoid high-cost operations through memory caching
　 PHP usually plays an important role in retrieval and data analysis, and these operations may cause performance degradation. In fact, some operations are completely unnecessary, especially repeatedly retrieving some commonly used static data from the database. Consider using the Memcached extension for short-term caching of data. Memcached's extended cache works with the libMemcached library to cache data in RAM and also allows users to define the cache period, helping to ensure real-time updates of user information.
　English original text: http://www.phpbuilder.com/columns/php-performance-tips/Jason_Gilmore07122011.php3?page=1

The above introduces SQL performance optimization and PHP performance optimization to generate highly optimized code, including the content of SQL performance optimization. I hope it will be helpful to friends who are interested in PHP tutorials.