Application Layer Editing, Sledgehammer or Scalpel?
In comparison to traditional ways to install applications and other application delivery methods that have been around for quite some time – such as application virtualization – application layering technology is still in its early stages. Because app layering is relatively new, tools for editing existing layers are unfortunately sparse.
You might ask, “Why would I need to edit an application layer?” Well, you could find yourself needing to edit registry keys for an application layer because you want the application to behave differently. So, how would you edit registry keys for a layer that is already created? The default answer for all layering vendors (assuming they can even edit layers, you should ask!) is to put the layer back into capture or packaging mode and make your registry changes there. Sure, this will work, but this is a “sledgehammer” approach when a “scalpel” may be better. When you put a layering tool into capture mode, it records all changes that happen to the operating system. This is a bit heavy-handed when you’re only trying to make a single registry key change.
Windows is noisy. When you put a layering product into capture mode, it is trying to ignore as much of the noise as it can. You can see how effective layering vendors are at ignoring static by looking at how large your layers are for even the smallest applications. Again, a good question to ask of your layering vendor is, “How big is Notepad++ as a layer — closer to 60 MB or more like 1.2 GB?” If layering solutions playback too much noise when layering an application, they can destabilize the OS. So, vendors have two options. They can either ignore the noise on capture and create a smaller layer, or they can capture all the noise and ignore noise on playback, resulting in inflated layers. No matter what a vendor says, they will capture at least a little bit of noise into the layer. This is the risk of putting a layer back into capture mode.
Read the entire article here, Application Layer Editing, Sledgehammer or Scalpel? | Liquidware Blog
via the fine folks at Liquidware Labs