Win7 fat-trimming: the bigger picture

[f0dder]

Hey everybody, been lurking around for a while, and now it's time for my first post

I've been sifting through a lot of posts here, including 30+ page ones, launching google queries, and looking at MS tech documentation. I believe I have a decent general overview of how things fit together, but there's still some pieces missing; my google-fu might not be hard enough, or I might have skimmed some topics here too quickly; in that case, I apologize.

Still, I reckon it wouldn't be bad getting some of the nitty-gritty tech things in one thread here, where you don't have to deal with a boatload of posts about which components that are safe/unsafe to remove, how to find or use the tools, et cetera . Besides, I'm sure some of the questions can be answered off-top-of-the-head by some of the MSFN members that have spent more time on these topics than I, without having to dig through countless more pages of information (yes, I possess the virtue of laziness).

Some of the questions would probably be important if somebody was to create a vLite successor...

Without further ado, here goes, more or less random order:

"WIM tweak" (win6x_registry_tweak_bin_v1.1.rar) - as far as I can tell, this tool does "something with regards to ownership or permissions". Does it do it for files in the WIM, or only for keys in the registry hive? What are the security implications of all this, are the permissions/ownership reset when installing?

Vista vs. Win7 WAIK - I've seen several guides that say you should use the older WAIK version. Is this a general recommendation, or is it only required for vLite? If you copy the pre-win7 WAIK version of wimgapi.dll to vLite's folder, is using the Win7 WAIK fine - or are there issues with WIN7-WAIK wimmount.sys?

Is there a way to disable hibernate + pagefile pre-install? (I should think it's possible by editing the registry hive, but heard that setup re-enables the pagefile at least?)

Removing components with DISM: are they removed from the image file, or just "not selected for install"? For the components that can be removed with DISM, are there any advantage/disadvantage to using DISM over vLite? When removing packages with DISM, are any artifacts left behind (registry entries, disk files)?

ImageX vs. DISM - there seems to be a bunch of overlap between those two tools; on the other hand, it seems like ImageX can export an image to a new WIM but DISM doesn't have a (documented, at least) switch to do this. Other differences between the two tools? Is there any difference in mount/unmount performance?

Cleaning the "sources" folder: some guides say remove everything but setup.exe, install.wim, boot.wim - I guess the other files are only necessary when doing an upgrade from existing Windows, so when doing clean install from usb/dvd/whatever only these three files are necessary?

What are the implications of doing "nullify of winsxs-Backup"? I understand it reduces install and source-media sizes, but isn't this folder is the new version of the pre-Vista DllCache? Removing DllCache sometimes gave me some annoyances when installing/updating drivers or whatever.

How does mounting a WIM file work? The MSDN docs mention the use of a filter driver, but based on some simple performance tests I get the impression that mounting an image actually unpacks it, and unmounting re-packs? (although possibly only repacks the changed files). I put an install.wim on a ramdrive and mounted to a path on my harddrive - enumerating the files in the mount path was relatively slow. Putting the install.wim on the harddrive and mounting to ramdrive had much faster enumeration...

I know MS doesn't want you do distribute files from the WAIK, but does anybody know the redistributable status on wimgapi.dll? Considering that it's part of the SDK I would assume it's redistributable, but I couldn't find any mention in the WAIK docs mentioning redistributable rights.

[Kernelspoke]

Since I here now that Win 7. 7600 has been optimized to support majority of the applications around, I would like to leap to a lite version of Win 7. This guy has asked some really valid questions as I would also like to know the answers to them.

[Kelsenellenelvian]

Vista vs. Win7 WAIK - I've seen several guides that say you should use the older WAIK version. Is this a general recommendation, or is it only required for vLite? If you copy the pre-win7 WAIK version of wimgapi.dll to vLite's folder, is using the Win7 WAIK fine - or are there issues with WIN7-WAIK wimmount.sys?

You HAVE to use Vista-SP1 WAIK with vLite as it was NEVER (vLite that is) optimized or made for win7

I know MS doesn't want you do distribute files from the WAIK, but does anybody know the redistributable status on wimgapi.dll? Considering that it's part of the SDK I would assume it's redistributable, but I couldn't find any mention in the WAIK docs mentioning redistributable rights.

wingapi.dll is part of WAIK and although WAIK is a free download you cannot distrubute only parts of it.

Edited September 26, 2009 by Kelsenellenelvian