A free program for Windows, by Sir Garnon.
The Skyrim Performance Monitor is a utility used for tracking Skyrim’s system resource usage as it relates to INI settings and installed mods.
It will display graphs and information about the performance of your game, as well as provide you with a list of the most common settings that affect performance.
If you’re using a mod utility to launch the game, you may need to have the performance monitor start the alternate launcher first, and then start Skyrim from that particular launcher.
You can pause the monitoring while Skyrim is running.
You can save your current performance data for later comparison.