Preface

The PHP community faced a huge problem over decades: performance. No matter how powerful hardware they got, in the end, PHP was a bottleneck in itself. With PHP 5.4.x, 5.5.x, and 5.6.x, PHP's performance started to improve, but still it was a huge problem in high-load applications. The community developed caching tools such as Alternative PHP Cache (APC) and Zend OpCache, which cached the opcode for high performance, and these tools had a good effect on the performance.

To get rid of the performance issues of PHP, Facebook built their own open source tool called HHVM (HipHop Virtual Machine). According to their official website, HHVM uses the Just In Time (JIT) compilation to achieve superior performance while maintaining the development flexibility that PHP provides. HHVM had great performance compared to PHP, and it is widely used in production for heavy applications such as Magento.

PHP went to war with HHVM using PHP Next Generation (PHPNG). The whole purpose of PHPNG is to increase performance and focus on the rewriting and optimization of the Zend engine memory allocation and PHP data types. People around the world started benchmarking PHPNG and HHVM, and according to them, PHPNG was outperforming HHVM.

At last, PHPNG was merged with the master branch of PHP, and after a tremendous amount of optimization and complete rewriting, PHP 7 was released with huge performance improvements. PHP 7 is still not JIT, but its performance is great and similar to HHVM. This is a huge performance increase from the older versions of PHP.