Apache vs. IIS PHP performance comparison

Question

Does anyone know of any links to realistic performance comparisons of IIS vs. Apache for PHP hosting?

I am looking to utilise existing infrastructure for a change of technologies from .NET to a PHP application but I cannot find any information about PHP hosted on varying platforms. There is heaps out there about IIS vs. Apache in general, or ASP.NET vs PHP .. or any other language server vs server, language vs language but no server/language vs server/language.

My current direction is to use PHP with FastCGI.. looks pretty good. Just need to justify it or find a compelling reason to reject the big cuddly MS monster that I'm used to.

UPDATED

Windows environment would be Win2k3 running IIS6 with FastCGI serving the PHP extension. Also planning to use eAccelerator or similar script cache.

Answer 1

PHP Best Practices article -- Differences between PHP on WIMP and PHP on LAMP

Some of the differences you may encounter when developing with PHP on Win/IIS vs Linux / Apache.

The most obvious difference between WIMP and LAMP is definitely performance.
For years there has been an obvious performance advantage of LAMP over WIMP.
Only recently is their even a chance of closing that gap.
There are currently 2 projects underway that may help.

Currently available is IIS7 which is reported to have had PHP performance enhancements built in with collaboration from the ZEND team.

An upcoming projects involves Microsoft engineers working with PHP engineers to get the next version of PHP (PHP5.3 which is not yet available at this time) to perform much better in IIS. This will no doubt make some progress toward WIMP catching up with LAMP in performance.

Answer 2

FastCGI on IIS will significantly increase the performance and will be comparable to that of LAMP. The difference will be in details, which are hard to pick and depends on what your configuration is and on what you scripts do. For example, file access on Windows is much slow than on Linux because of NTFS's ACL checks.

There is nothing particularly wrong with the Windows web stack. The only big reason I'd think of using Windows over Linux when human experience doesn't matter would be SQL Server. Otherwise WAMP, WIMP and LAMP perform comparably and performance differences won't show up until heavy load.