A very hot topic among Vista user is the seemingly robust size of the WinSxS directory and it’s ability to grow with apparently no limit. While most users are not too overly concerned with disk space and have GBs to burn, the majority (myself included) still like to keep the footprint of the operating system as small as possible. I have posted on the topic a couple times before:
I came across an interesting post today by Michael Beck on the Engineering Windows 7 blog about Disk Space. As I began to read the post I realized that this was by far the best explanation of the WinSxS directory to date. I encourage anyone and everyone who is interested in understanding the WinSxS directory in Vista to give this post a thorough read through. You may just change your mind about moving or deleting the WinSxS directory. A couple interesting tidbits to wet your appetite:
The Windows SxS directory represents the “installation and servicing state” of all system components. But in reality it doesn’t actually consume as much disk space as it appears…
In practice, nearly every file in the WinSxS directory is a “hard link” to the physical files elsewhere on the system—meaning that the files are not actually in this directory.
The WinSxS directory also enables offline servicing, and makes Windows Vista “safe for imaging”.
While it’s true that WinSxS does consume some disk space by simply existing, and there are a number of metadata files, folders, manifests, and catalogs in it, it’s significantly smaller than reported. The actual amount of storage consumed varies, but on a typical system it is about 400MB.