Exponential Algorithm In Windows Update Slowing XP Machines

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 Each additional superseded patch would double the time taken to process the list.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."

Remove, replace with apt

[kthreadd]

This is clearly the right time for Microsoft to completely rewamp the update system in XP; and what could possibly be better than to just remove the whole thing and import an already working package system from Debian?

Re: O(2â) should be avoided

[Anonymous Coward]

And how exactly does Slashdot not have full Unicode support?

Re:On purpose?

[X0563511]

I'm really - I mean really, uncomfortable with the thought of Microsoft planning this kind of thing 12 years in advance...

Re:Best way to force an upgrade

[TangoMargarine]

Mainstream support ended on April 14, 2009. They've been pumping the dead horse full of adrenaline ever since to keep it from falling over.

Standard MS Joke

[Naatach]

How many Microsoft Engineers does it take to change a lightbulb? None. They just redefine darkness as the new standard.

Re:No Sympathy

[TheRealMindChild]

Just shoot the control panel. Door will just open

Re:Remove, replace with apt

[mlw4428]

That's right. I can just then run an apt-get dist-upgrade and I'll have a non-booting system in mere hours! No more waiting for pesky Windows releases.

Re:No Sympathy

[chromas]

Well, then good news! Windows XP is just four months away from being perfect.

Re:No Sympathy

[Anonymous Coward]

Be sure to use bullets. Using a laser will just make the blast doors close.