DotNetNuke on Windows Azure Websites performance

Question

I am evaluating the Windows Azure WebSites Preview (WAWS I think, not sure with all these changing names and acronyms that Microsoft loves to mutate on) with DotNetNuke (DNN) which I am also using for years on a "non cloud" V-Server. Installation was a breeze. I only tried the free shared instance and I have tested with 1 and with 3 active instances with similar results.

First hit performance always was a problem with my previous DNN installations, when a website was idle for a while (15 minutes or so) the process would stop and then the next unlucky visitor will wait at least around 20 seconds. With some IIS tweaking it was possible to minimize this problem but I had the best results with a monitoring service that will request a page from DNN every five minutes and keep the process up.

While surfing the DNN page usually performs well on WAWS, I immediately noticed that the "first hit" problem is an issue with DNN on WAWS so I configured a monitoring service for the page. That did not help and the monitoring service will always report that the site is down. Almost as if WAWS was trying to avoid keeping the site up since it detected that only a monitoring service was requesting the page.

Also, when navigating on the DNN pages and then pausing for just a minute or two, I will often get an "Internet Explorer could not load this page" error with no specific error code.

Do others have experience with the DNN performance on WAWS or maybe know why the "first hit" is such a problem?

Answer 1

I suspect that Microsoft is actively trying to avoid the keep-alive tricks that many ASP.Net devs use. WAWS, like many shared hosting platforms, relies on only having a certain number of active websites on the server at any one time in order to achieve higher server densities and keep the cost of hosting under control. This is one of the reasons that they can offer this service for free.

Answer 2

I think what you want to look into is "keep alive."

What you are experiencing is the ASP .NET process getting killed for your application due to inactivity. When the process isn't in memory and the site is accessed IIS has to spin it back up which is the 10 - 20 second lag you get upon accessing your site as the process gets up again and/or just in time compiles.

You can schedule some 3rd party monitoring services to check your site every 10 minutes via an HTTP request that will keep your site up. Just pinging it will not keep it up.