Degrading performance when IIS/ASP app in virtual directory is converted to new website with dedicated IP

Question

I have an asp.net application running in a virtual directory under the default IIS web site.

After deploying this to its own website with its own IP address (on the same machine), performance degrades drastically.

My first guess may be that this is perhaps some sort of a routing issue, but I am not too sharp on the networking end of things, so I'm not sure what I should start looking at first. Or, maybe it is something else entirely?

UPDATE: Everything else in this scenario has stayed the same, essentially, a New Website with a static ip address was created, pointing to a new folder where all of the files from the virtual directory were xcopied to.

The entire site seems slow (but it varies up and down over time)....images, scripts, you name it. No terribly unusual memory or CPU consumption.

Is it possible for it to be some sort of a routing issue? And if so, how would a person go about diagnosing this?

Answer 1

You should use ASP.Net tracing to detect if your application is slow or problem is in network configuration.

You can enable tracing on page level, by adding Trace="true" to page directive in aspx:

<%@ Page Trace="true" %>

or you can alternatively enable trace for whole application through web.config:

<configuration>
  <system.web>
    <trace enabled="true" requestLimit="40" localOnly="false"/>
  </system.web>
</configuration>

Check MSDN articles on ASP.Net Trace for more details.

My bets (problems I had):

1. ASP.Net configuration problems
   • Defaults fore some important parameters in machine.config are very low You should check following parameters:
     • maxconnection
     • maxIoThreads
     • maxWorkerThreads
     • minFreeThreads
     • minLocalRequestFreeThreads
   • Here is description and recommended values: IIS 6.0 Tuning for Performance
2. Database problems
   • database on another server and application was very chatty (lots of small queries)
   • database on another server and badly configured internal network that caused latency

3. Network configuration problem

   • check routing
   • call network admin

   Check this SO question for some more ideas: an ASP.NET performance bottleneck mystery