PHP Version Resolution

PHP has several different versions to choose from when downloading. That's VC6 X86 and VC9 X86.

First of all:
What is VC6?
VC6 is Legacy Visual Studio 6 compiler, which is compiled with this compiler.
What is VC9?
VC9 is the Visual Studio compiler, which is compiled with Microsoft's vs Editor.

So how do we choose which version of PHP to download?
If you are using apache+php under Windows, please select the VC6 version;
If you are using iis+php under Windows, please select the VC9 version;

There is non thread safe and thread safe version of the choice should also be troubling everyone,
First, literally: none-thread safe is thread-safe and does not carry out thread safety checks at execution time, thread safe is threaded, thread security is performed, To prevent new requests from starting the CGI execution of new threads to drain system resources.

To see how PHP is loaded, CGI does not say, too cross the ... Let's just say the ISAPI and fastcgi two load modes. It's hard to talk about ISAPI and it's hard to mention that Linux-based operating systems are working in multiple processes, and we're familiar with the Windows operating system that uses multithreading. Multiple processes and multithreading are not the same. ISAPI is a multi-threaded way to load PHP, but many of the usual extensions of PHP are developed under the multi-process working mode of Linux, then these extensions in the ISAPI will be problematic ...

fastcgi load PHP, can let the php-cgi process reuse, and not like CGI, every time re-unload and reload, resulting in a heavy waste of resources. Colleague FastCGI can allow several processes to be executed at the same time, which solves the problem that CGI consumes too much or the compatibility of ISAPI with PHP, which can improve the stability to load PHP well. FastCGI is performed on a single thread, so there is no need for thread security checks, and the thread safety check is eliminated instead, so if PHP is loaded with fastcgi (either an IIS server or an Nginx server), It is recommended to use the None-thread safe version of PHP.
The official does not recommend that you apply the non thread safe to the production environment, so we chose the thread safe version of PHP to use.

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