GDBT - Geodatabase Performance Toolkit

GDBT (Geodatabase Performance Toolkit) is a free extension (for both
ArcMap and ArcCat) that allows you to test the response time of
layers, generate load against a server, tune spatial indexes, and
visualize the state tree manager users (on ArcGIS server).

It's a great tool that should be part of ArcGIS Desktop core:

http://www.esri.com/software/arcgis/extensions/gdbt/index.html

If you already like and use it, or if you use it and like it, please
write your local ESRI account manager and request that GDBT become
part of ArcGIS Desktop core. Evidently not enough people who use it
are making their wishes known. ESRI sometimes rolls good sample/
example code into their core products, and GDBT is fantastic.

I don't work for ESRI--I'm just an enthusiatic user.

Dana