The name of the Zend engine is a combination of the names of Zeev Suraski and Andi Gutmans, two senior designers who worked as core developers in PHP. The purpose of the development was to develop a new script execution mechanism, and PHP4 is the first version of this new Zend engine. A practical product. In some special test environments, the execution speed of Zend (PHP$) is several to hundreds of times faster than PHP3 and ASP. This also means that the unifier of the website's back-end CGI interface must be PHP4 Zend. (Of course, technology is constantly improving, and new engines may appear one day.)
After more than two years of development, the Zend engine has become a generalized programming environment similar to VBA functions. It not only has traditional PHP The function function also adds the function of distributed objects (COM) and can be executed on different operating platforms. If it continues to develop with this potential, the terminator of VBA must be Zend.
When Zend was implemented on PHP4, it made the most complete commitment to the session, which was the biggest shortcoming before PHP3, and also added some future features, such as CyberCash... and so on.
In the opensource community, the only one that can maintain its momentum but has not yet been regarded as a competitor by Microsoft, PHP/Zend is the best example. It has completely left ASP behind and is developing towards a VBA environment. However, Microsoft only focused on dealing with Linux and did not pay attention to the threat from PHP/Zend.
The web server found that it was a request from PHP and needed to be parsed by the PHP engine (according to the file extension), so it sent it to the Zend engine of PHP4.
The Zend engine reads the file from the hard disk and sends it to the Zend online compiler (Run-time Compiler) for program literal translation. (Maybe the online compilation work can be omitted when Zend Compiler comes out in the future.)
The online execution unit (Excutor) of the Zend engine executes the compiled PHP program. And when necessary, find relevant modules to perform collaborative actions (such as XML, IMAP, ODBC...etc.).
Zend organizes the execution results into HTML files and sends them to the web server.
The web server sends the results back to the user's browser through the network.
There are currently four Zend products:
Zend Engine: Zend engine Zend engine currently only makes PHP4, providing cross-platform functions similar to Microsoft's VBA. The current popularity on the Internet has also provided the best testimony for the Zend engine. Among Zend's four major products, this is currently the only mature product.
Zend Optimizer: Zend Limiter re-adjusts the core of PHP to make PHP program execution more efficient. It can mainly speed up the execution of PHP code and reduce the burden on the CPU, reducing latency.
Zend Cache: Zend Cache caches the PHP program into the memory of the web server, so that the system no longer has to read the PHP program from the hard disk, which can greatly shorten the system's response time and reduce the load on the network. Data stored in the Cache does not even need to be translated, reducing processing resources.
Zend Compiler: Zend compiler This is probably the ultimate weapon of Zend. It allows PHP program code to be compiled and exist in the form of Zend Intermediate Code (ZIC, Zend Intermediate Code).
It can protect the PHP source code from being seen by users, so that the PHP source code is safe. It is expected that after the emergence of this product, it will have a considerable impact on the entire network. PHP code object libraries will be available everywhere, and the software industry will also provide relevant function libraries or object libraries to PHP programmers. By then, there may be a PHP vs. Java situation.
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