MiniProfiler has already been integrated into Umbraco V6. Therefore, this package is deprecated and only valid for Umbraco 4.7.x
MiniProfiler for Umbraco is based on the http://miniprofiler.com/ from Sam Saffron and will help you to profile your macros and your SqlServer and SqlCe.
Please visit http://profiler.jlusar.es to see a live example of how it works. Notice that no macro has been cached so you can see what happens on every request. You can also have a look at the source code on https://github.com/jorgelusar/miniprofiler-for-umbraco
MiniProfiler comes in two versions, one compatible with Umbraco 4.8, SqlServer and SqlCe, and another one compatible with Umbraco 4.7.x and only SqlServer.