When I think about performance with DotNetNuke®, my first thought is no longer, "What can I do?" Now, my first thought is more like, "How can I do this with PageBlaster?"
If you are not yet familiar with PageBlaster, it is a DNN module by Snapsis that increases performance of the web site in a variety of ways. Most notably, the performance increase in the recent version (3.03.02) is due to caching, compression, and the merging of CSS and JS files into one.
I could go into greater details of how else it increases performance, but those should suffice for now.
The more you use PageBlaster, the more you begin to realize just how much John Mitchell knows about ASP.Net performance, and more importantly, performance with DotNetNuke®. So, naturally, when I read a post from him about performance settings in DotNetNuke®, I take it to heart - and yes, I believe it.
Basically, when you log in as a Host, you are able to access a ton of settings in the Host Menu > Host Settings page. Of those features, you will find a section labeled "Advanced Settings". The performance settings can be found in a sub-section intuitively named "Performance Settings".
Here are the recommended settings that John Mitchell says to use. I would trust his recommendation, as he has a huge insight and knowledge to the inner workings of the DotNetNuke® core that most of us will never have.
Page Persistance: Page
Module Caching Method: Memory
Performance Setting: Heavy
Authenticated Cacheability: Public
Compression Setting: Deflate
Compression Level: 5
Use Whitespace Filter: unchecked
John's post says that the compression setting doesn't matter. However, it does matter if you want your compression to scale. That is why I chose "deflate".
If you want a greater description of why each of these settings are used, see the reference below.
I employed these suggested settings a couple of days ago, and I am really enjoying the benefits!
Snapsis Forum Post on 02/11/2007