One of the other common asks we receive is to enable .NET client applications to launch faster in "cold startup" scenarios. "Cold startup" scenarios occur when no other .NET client applications are running (or have recently run) on a machine, and require the OS to load lots of pages (code, static data, registry, etc) from disk. If you are loading a large .NET client application or library, or are using a slow disk, these cold startup scenarios can require many seconds for your application to start.

This summer we are going to ship a servicing update to the CLR that makes some significant internal optimizations in how we optimize our data structures to cut down on disk IO and improve memory layout when loading and running applications. Among many other benefits, this work will significantly improve the working set and cold startup performance of .NET 2.0, 3.0 and 3.5 applications and will dramatically improve end-user experiences with .NET-based client applications.

Depending on the size of the application, we expect .NET applications to realize a cold startup performance improvement of between 25-40%. Applications do not need to change any code, nor be recompiled, in order to take advantage of these improvements so the benefits are automatic.