Question:

Hi David,

I am developing an ISAPI Filter to prove the N+1 Architecture.There will be few static sites, few dynamic sites and few cgi perl script sites will be there. Can you please tell me how ISAPI performs for CGI Perl Scripts.

Thanks and Regards.

Answer:

How ISAPI performs on IIS completely depends on how its author writes it. ISAPI is a thin wrapper that allows you to run raw Win32 code on IIS, so it is as fast as you can get. Thus, the real question is whether you can write the ISAPI Filter performantly for your N+1 experiment?

I really do not know what you plan on writing, so I cannot offer any additional advice other than if you do things incorrectly, ISAPI Filter can also strangle/crash IIS very easily. With power comes responsibility. Choose wisely.

Now, I can say that launching CGI Processes to execute scripts will likely be one of the slowest part of the website, so you want to optimize and use ISAPI versions of everything. So, you want to use an ISAPI version of Perl to execute Perl Scripts.

You may want to browse through other blog entries for general thoughts. Some of them include:

//David