Errors in "Tweaking Windows XP" guides.

[Tor]

There is a couple of errors in the "Tweaking Windows XP" guides. I have looked and used the guides several times when reinstalling XP. I guess others may be using it as reference, as I do, so I suggest you update it.

The following tweaks are wrong according to other websites, such as www.tweakxp.com

Part 1, page 5:
Tweak #9 - Memory Performance Tweaks
Input/Output Performance

This tip is wrong. The DWORD value IOPageLockLimit has no effect in Windows XP. The value was removed as of Windows 2000 SP1.


Part 2, page 5:
Tweak #10 - QoS Tweakage
"One of the differences between QoS and TCI is that it is possible to reserve bandwidth for QoS applications. This is great if you are using QoS applications, but if you don't use any, it means that a percentage (20% by default) of your bandwidth is sitting unused."

This is wrong. The 20% will only be used if there are QoS aware applications running. Otherwise all 100% is fully available (hence the "reserved").

Edit: I can see that QoS "tweak" is even in the sticky post in this forum too.

[sKuLLsHoT]

i am neither agreeing nor disagreeing, but can you backup your statement re QoS with some sort of evidence?

[Grim Reaper]

no...even if they are not running it still reserves it...ive seen in some cases that ppl still get same speeds as they did before they installed XP, but ive only seen 1 case of this...all others, the speeds have increased...ill believe otherwise if you give me some evidence...

[Tor]

For the QoS:

Description from TweakXP, tweak: Modify bandwith reserved for QoS-aware programs:

"When a QoS-aware program is in use it will reserve the allocated amount of bandwidth and that will take away form other non QoS-aware programs. However, once the QoS-aware application is closed or closes the network connection, the bandwidth reservation is released. This is done by a series of PATH and RESV refresh messages sent back and fourth over the connection. Once these messages are no longer detected, the data flow is closed and the reservation of bandwidth is eliminated.

Original Tweak was written by BigBrother but was rewritten after it was found to be incorrect."


The same description from Microsoft:

"When Soft state is established, nodes send PATH and RESV messages periodically (usually about every 30 seconds) to refresh the reservation and path state. If no matching refresh messages arrive before a certain cleanup interval elapses, the state is deleted."

--------------------

For IOPageLockLimit:

From TweakXP forum:

"*shrug* I know, lots of sites repeat the same information. Sorry, but they're wrong.

XP is not "2K", it is a lot of revisions on top of 2K. And in any case, Win2K SP1 and SP2 didn't use this value either!

(Do you think that EVERYthing that was in NT 3.1 got carried forward to now, over a decade later? Even obscure mechanisms that were put in place to solve a problem back in the NT 3.x days, and that no longer serve a purpose?)

As for the resource kit doc - obviously it needs to be reviewed more carefully for each rev of the OS.

Here's evidence: Go to www.sysinternals.com and pick up MarkR's "strings" utility. Run it against NT4, Win2K, and WinXP versions of ntoskrnl.exe. You might find it halpful to limit the output with the -n option, say with a value of 12 or so, since the string we're looking for is longer than that. Redirect each into a text file, so you have, say, nt4.txt, win2k.txt, and winxp.txt.

Now open each in notepad and look for occurrences of "IoPageLockLimit".

In the "strings" from the NT4 version of ntoskrnl.ese, you'll find it. Nearby you'll notice a few other familiar names, like DisablePagingExecutive and LargeSystemCache. You are looking at the text strings that are hardwired into the exec, by which it looks up these registry values. They're all in a group because all these things are in a table, along with the pointers to the locations where they're stored.

You'll also find IoPageLockLimit in the Win2K base release.

Now look at the Win2K SP1, SP2, and XP versions. You won't find IoPageLockLimit there any more. You will find the others.

(In Win2K SP1 the mechanism was still there, but apparently controlled by a different registry value, IoPageLockPercentage. They threw the whole thing out as of Win2K SP2.)

This isn't completely definitive; the init code could be synthesizing that string out of smaller parts, but why would they do that for this, and not for e.g. LargeSystemCache?

If you still don't believe it, try running MarkR's "regmon" tool, starting at boot time, logging all registry accesses to a file. Search the resulting log for references to DisablePagingExecutive and LargeSystemCache, which you will find, and for IoPageLockLimit, which you won't as of win2k sp1."

[Tor]

Nobody from tweaktown seems to care that they give away wrong tweaks??!?

[Anonymous]

In the section on Prefetch Parameters, I think there's an error. The author mentioned that the value 5 worked best for him, but I have only been able to find four possible states for the prefetch:

0 (0x0000) = Disabled
1 (0x0001) = Boot Files Only
2 (0x0010) = Application files only
3 (0x0011) = Both Boot and Application Files

Since the value is stored as a hex DWORD, the author's recommendation to use the value 5 (0x0101) would be equivalent to a value of 1, since I can't find any evidence that the Session Manager reads anything higher than the 2**1 bit for the EnablePrefetcher value.

Of course, Msoft has been very sparse with their documentation on this feature - if you have any more detailed documentation on how it really works, please let me know at [email protected]

[heinz57]

I use this Reg entry set to [32] works great.

[papajim]

I am running Win XP Pro and was having problems with slow networking, setting too 0 increased network speed from ( 1meg wirles ) 144k to 756k. So in my case it did have a big affect!

[Wiggo]

The thing that seems to stand out most about XP is that it molds itself differently to different hardware combinations and where one tweak will work for some and not for others or will work with a slight change seems to bare this oppinion of mine out on this os. :smokin:
<center>:cheers:</center>

[Beefy]

I agree.. with all the tweaks that I tried from the guide, they all worked flawlessly...

[Grim Reaper]

there we have it...these tweaks DO work...if they don't work for you then just stfu with ur crap...sorry but saying that we don't give a **** about giving out false info/tweaks is bull and that it isn't false at all, crawl back under your rock if your not going to be a useful/nice member of TweakTown..you could have raised this but you could have left the nastyness out of it

[heinz57]

[ Grim Reaper ] Who was last post meant for ?.

[Grim Reaper]

pretty much tor, sorry for not stating that...

thread closed...PM me if you have any problems