I’ve followed Carsten Keutmann’s blog on and off over the last few years. When he writes, he writes great stuff. (Write more often, Carsten!)
I had previously plugged Carsten’s SharePoint Manager 2007 tool, and he’s released updates to it since I’ve last looked at it. This is a must-have tool for serious developers. It lets you explore the object model with a nice Windows-based interface and even make changes to the data. THIS IS A SERIOUS TOOL. Don’t try to use it if you don’t understand the SharePoint Object Model very well, as any changes you make could render your application unusable.
The SharePoint Manager 2007 is a SharePoint object model explorer. It enables you to browse every site on the local farm and view every property. It also enables you to change the properties (at your own risk). This is a very powerful tool for developers that like to know what the SharePoint holds of secrets.
One of the big "gotchas" in coding against the SharePoint Object Model is not disposing of resources properly. In relatively little time, you can find that your server is cycling itself to free up resources, with no apparent reason. The first thing you should check is your own code.
Roger Lamb has written an excellent, in-depth article called SharePoint 2007 and WSS 3.0 Dispose Patterns by Example about how to fix these issues. When my client had memory leak issues, they first wanted to blame the third party Web Parts that they had installed and they uninstalled them. No joy. After much back and forth with Microsoft (I was out of the loop on much of this), they were pointed to Roger’s post. Making all of the changes that Roger recommended solved the problems.
These weren’t "big deal" Web Parts, either, but they were called frequently. Every time that they were called, they held onto a little bit of memory until everything was brought to its knees. No matter that they were running big iron for their farm; memory is finite, and eventually you will use it all up.
Another excellent resource is an article that Roger references in his post from Stefan Goßner entitled Dealing with Memory Pressure problems in MOSS/WSS.
While computing has changed drastically since my early days of writing assembly and FORTRAN, smart use of memory never goes out of style!