Peter asks: I have one of let's say 10 app layers activated, and using Regmon shows that there are LOTS of reg seeks by services.exe that result in a "Not found". Wondering what's going on, and how I can stop these many reg seeks.
One of the design principles of SVS is to keep the technology as small and unobtrusive as possible. So in the original release, we chose to pass through registry lookups rather than trying to "proxy" or "cache" them. The only way for this to work was to recursively search every active layer when a process tried to read or open a key. That's why you see what you mention above.
In practice, we observed that a different approach was necessary to be performant. In SVS 2.1, Altiris has implemented a registry cache. The result is a slightly more complex design, but a design that preserves the registry performance of native Windows. This one change resolved all of the performance-related support issues that we had with SVS 2.0.
You can check out the improvement for yourself with SVS 2.1 Beta 1!