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Exponential Algorithm In Windows Update Slowing XP Machines 413

Posted by samzenpus
from the no-pep-in-your-step dept.
jones_supa writes "An interesting bug regarding update dependency calculation has been found in Windows XP. By design, machines using Windows Update retrieve patch information from Microsoft's update servers (or possibly WSUS in a company setting). That patch information contains information about each patch: what software it applies to and, critically, what historic patch or patches the current patch supersedes. Unfortunately, the Windows Update client components used an algorithm with exponential scaling when processing these lists. Each additional superseded patch would double the time taken to process the list. With the operating system now very old, those lists have grown long, sometimes to 40 or more items. On a new machine, that processing appeared to be almost instantaneous. It is now very slow. After starting the system, svchost.exe is chewing up the entire processor, sometimes for an hour or more at a time. Wait long enough after booting and the machine will eventually return to normalcy. Microsoft thought that it had this problem fixed in November's Patch Tuesday update after it culled the supersedence lists. That update didn't appear to fix the problem. The company thought that its December update would also provide a solution, with even more aggressive culling. That didn't seem to help either. For one reason or another, Microsoft's test scenarios for the patches didn't reflect the experience of real Windows XP machines."
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Exponential Algorithm In Windows Update Slowing XP Machines

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  • by s_p_oneil (795792) on Monday December 16, 2013 @06:03PM (#45708373) Homepage

    That's the best way to force users to upgrade that I can think of. They're already planning to end-of-life it. After EOL, they can simply start adding empty patches to the update system until it drives left-over XP users to upgrade. ;-)

  • by Anonymous Coward on Monday December 16, 2013 @06:05PM (#45708397)

    Yeah, four months before the final end of support date I'm sure they have a copious budget for massive rewrites on their three-major-versions-old legacy product.

    But good news: after next April, just kill off the update checker entirely, because there will never be an update again! Problem solved. You're welcome.

  • Re:No Sympathy (Score:5, Insightful)

    by viperidaenz (2515578) on Monday December 16, 2013 @06:07PM (#45708443)

    So someone thought it was a good idea to upgrade a security system with software that will have no security support in 4 months time?

  • by mlts (1038732) on Monday December 16, 2013 @07:00PM (#45709017)

    It killed my Web browsing virtual machine until I used an offline update utility and fixed it manually.

    Yes, XP needs to die, because it is made to deal with threats from 2000-2001, with added security patches strapped on as the need arose. Windows 7 and newer help address this issue.

    However, I know plenty of places where XP is used that can't be fixed by a upgrade or platform change. Embedded stuff for example. Another are dedicated machinery that interfaces with a PC, does have newer drivers, and likely will not get newer drivers. A friend's $3000 sewing machine is one example.

    Another person's CNC wood mill is another item. So, those machines are stuck with XP pretty much for good, because who is going to throw out a perfectly functioning mill just because it requires a legacy OS? Even some CD/DVD duplicators only will interface with XP, and moving to Vista or newer will be an exercise in futility.

    So, XP in a lot of cases is here to stay, for better or worse.

  • Re:No Sympathy (Score:4, Insightful)

    by Luckyo (1726890) on Monday December 16, 2013 @07:04PM (#45709069)

    Many reasons.

    1. It's light enough.
    2. It's air gapped.
    3. It's secured via elimination of infection vectors.
    4. It's needed for legacy reasons.
    5. Etc.

  • by houstonbofh (602064) on Monday December 16, 2013 @07:18PM (#45709241)

    Is everybody stupid. XP is fast. Faster than all the current consumer grade PC OSes

    I think that is what this patch... Sorry... BUG is supposed to fix.

  • Re:No Sympathy (Score:3, Insightful)

    by saleenS281 (859657) on Monday December 16, 2013 @08:09PM (#45709681) Homepage
    None of those reasons explain why the product can't run on Windows 7.
  • by 10101001 10101001 (732688) on Tuesday December 17, 2013 @01:10AM (#45711393) Journal

    Yes, XP needs to die, because it is made to deal with threats from 2000-2001, with added security patches strapped on as the need arose. Windows 7 and newer help address this issue.

    Help address this issue..except not really. :/ Windows 7 was made to deal with threats from 2009-2010, with added security patches strapped on as the need arose. Windows 8 was made to deal with threats from 2012-2013, with added security patches strapped on as the need arose. You see a trend? The biggest things that consistently have to be done, no matter what version of Windows you use, is to (a) use Internet Explorer/Adobe Flash as little as possible (directly or indirectly through its rendering engine) and (b) keep as much of your software as possible up to date.

    That MS has chosen to not push more updates for Windows XP is the only real major thing hindering (b), but that speaks relatively little of XP. The only other major, possibly, beef is the hassle of installing so many incremental security patches. That's a major reason, of course, for Service Packs and slipstreaming.

    Nah, really, the only place XP needs to "die" is in that hardware has continued to evolve and XP has been left out of a lot of developments, in large part because fundamentally some things didn't exist when XP was released. That Windows 7/8 already exists and supports said hardware as part of a new system...then XP can "die" when you switch to a new system inherently. But, that still leaves plenty of years for fully functional hardware to keep using XP for a long while.

    It reminds me of a funny statement from Woz in "Accidental Empires" about how he couldn't wait for Moore's Law to reach its limit, so hardware would stop changing and schools could afford to spend the money on hardware that'd be around for 10-20 years like most other equipment. Ignoring that the actual time scale has shifted so much because of how cheap computers, not the PCs envisioned, have gotten, the mindset that old software shouldn't reasonably be supported for 10-20 years does sort of kill a lot of good ideas when it comes to reasonably using computer hardware. I guess there's always a long-term support contract with IBM and Linux...

The superior man understands what is right; the inferior man understands what will sell. -- Confucius