ASP.Net application runs slow at first time

Question

I have a web application written in ASP.Net 3.0 using C#, the production machine is a windows server 2003 with IIS 6.0 and sql server 2005.

Application Structure

The following shows the structure of my ASP.net web application:

root application in IIS (//localhost/es) includes the common pages, for instance: master pages, theme, user control, images folder. number of sub-projects under the root application (//localhost/es/sub-project). delete web.config in sub-projects assemble files of sub-projects is under bin folder of root application (sub-project properties >> compile >> build output path: ..\bin\ my application is a 3–tier web application(Biasness layer ,Data layer and Presentation layer. Also, every aspx page has its code behind cs file)

IIS Settings

Application pool Recycling Worker Process after "1740 in minutes" Idle timeout worker processes after being idle "20 in minutes" Ping worker process every "30 seconds"
Startup time limit for worker processer "90 Seconds" Shoutdown time limit for worker processer "90 Seconds"

Application Configuration
Cache limited ASP files in memory "500"

Cache limited ASP files on disk "2000"

Deploying Application:

I publish the web application with all its files to production server.

The Problem :

The application runs pretty slow at the first time, it takes upwards 10 seconds to load, however every at the next time a page is requested it's be faster. I believe that the first time a page is requested, it compiles and it usually takes more time than the other requesting, because the page is in the Cache Memory. The question here is why it's take along time when compiling the page at first time?

Attempts to solve the Issue :

I tried to do the following :

• Deploying a copy of the required files to production server.
• Changed IIS settings, changed Idle timeout shut down of worker process
• Turn off Tracing
• Turn off Session State
• Disable View State of a Page
• Set debug=false in web.config
• Creating a hello world sub-project under the root application , it takes 5 seconds .
• Creating separate hello word web application , as above it takes long time to load.
• Remove the code in the page_load event handler , but it didn't affect on the performance.
• Publish only the needed file of the root application (no code written in the code behind), and all file in the source code of sub-project (code is in the code behind) ,

However, the application still starts of slow but then it gets faster.

Please help to diagnose and solve this problem.

Answer 1

In addition to what sky said, you could run a "warmup script" as the last step of your deployment process. Although this won't speed up the time needed for the first compilation, using such a script would at least prevent users seeing a slow startup. Have a look here for an example of such a script: http://programmerramblings.blogspot.com/2008/09/aspnet-site-warmup.html

Another reason why the very first request to your application is slow could be that IIS has to start the asp.net worker process during the very first request. This should however not affect first requests to other pages.

Answer 2

publish the website, which precompiles, as opposed to copying it.

The behavior you are experiencing is normal.