Something faster than HttpHandlers?

Question

What is the fastest way to execute a method on an ASP.NET website?

The scenario is pretty simple: I have a method which should be executed when a web page is hit. Nothing else is happening on the page, the only rendered output is a "done" message. I want the processing to be as fast as possible.

Every single hit is unique, so caching is not an option.

My plan is to use an HttpHandler and configure it in web.config (mypage.ashx) rather than a regular .aspx page. This should reduce the overhead significantly.

So my question is really: Is there a faster way to accomplish this than using HttpHandlers?

Answer 1

Depending on what you're doing, I wouldn't expect to see a lot of improvement over just using an HttpHandler. I'd start by just writing the HttpHandler and seeing how it performs. If you need it to be faster, try looking more closely at the things you're actually doing while processing the request and seeing what can be optimized. For example, if you're doing any logging to a database, try writing to a local database instead of across a network. If it's still not fast enough, then maybe look into writing something lower level. Until that point though, I'd stick with whatever's easiest for you to write.

For reference, I've written an ad server in ASP.NET (using HttpHandlers) that can serve an ad (including targeting and logging the impression to a local database) in 0-15ms under load. I thought I was doing quite a bit of processing - but that's a pretty good response time IMHO.

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Update after several months:

If you clear all the HttpModules that are included by default, this will remove a fair amount of overhead. By default, the following HttpModules are included in every site via the machine-level web.config file:

• OutputCache
• Session (for session state)
• WindowsAuthentication
• FormsAuthentication
• PassportAuthentication
• RoleManager
• UrlAuthorization
• FileAuthorization
• AnonymousIdentification
• Profile
• ErrorHandler
• ServiceModel

Like I said above, my ad server doesn't use any of these, so I've just done this in that app's web.config:

<httpModules>
   <clear />
</httpModules>

If you need some of those, but not all, you can remove the ones you don't need:

<httpModules>
   <remove name="PassportAuthentication" />
   <remove name="Session" />
</httpModules>

ASP.NET MVC Note: ASP.NET MVC requires the session state module unless you do something specific to workaround it. See this question for more information: How can I disable session state in ASP.NET MVC?

Update for IIS7: Unfortunately, things aren't quite as simple in IIS7. Here is how to clear HTTP Modules in IIS7

Answer 2

I'm not sure what your exact scenario is, but if all your page is doing is processing some data, you don't really need an aspx page or an http handler at all. You could write an ASMX web service or WCF service to do what you need and this would most likely be less overhead. The WCF service doesn't even have to be hosted in ASP.NET. You can host it from a Windows service or console app, and call it in-proc using named pipes. This would probably reduce the overhead for calling the data processing code significantly.