Exponential algorithm slows down Windows XP

The developer of Windows Update, Doug Neal (Doug Neal), explained why recently many Windows XP users have performance problems after installing fresh updates.

The study of logs from “inhibited” machines showed that the problem lies in the inefficient method by which the Windows Update Agent module processes long lists of previous updates. The processing time of lists increases exponentially with each new update. In other words, the processing of a new update takes twice as long as the previous one.

In the history of Windows XP, a huge number of patches were released, so that when processing a list of 40+ old updates, the svchost.exe process starts consuming a lot of CPU resources, and this noticeably affects the overall system performance.

The situation is observed mainly on Windows XP systems with an IE6 or IE7 browser installed, but not with an IE8 browser. Due to security requirements, Internet Explorer has the right to build the above chain longer than is normally allowed for Windows Update. Over time, this exception led to a problem due to a previously unknown bug in the Windows Update Agent.
')
Microsoft Security Response Center gave permission to reduce the list of processed updates, and the developers of Windows Update tried to fix the bug. In October of this year, they reduced the list on the backend side, but it didn’t help: “It turned out that the Windows Update Agent is pretty smart and it tricked us,” Doug Neil writes, “so the problem persists for most affected users.” A more complete change in the backend was made in November, and another one in December. Unfortunately, the problem still could not be fixed.

Unfortunately, the update packages are released once a month, so the next attempt will not work until January. Doug Neil assures that this problem now has the highest priority - and the right (and most intelligent) people have been thrown at its solution. An official KB newsletter will be released soon with a more detailed description of the situation, but there is no official way around it yet. Is that permanently disable Windows Update.

On the forums they joke that Microsoft has found the perfect way to get Windows XP users to upgrade to newer versions of the operating system. Official support for the most long-lived operating system in the Microsoft line comes to an end in April 2014, and before that it’s enough to release a dozen empty updates.

UPD. Comment by Alexey Solomin ( IRainman ): “In Windows 7, you can do the tail cleaning for Windows Update through the Disk Cleanup tool, the item“ Clean Windows Updates ”, this feature was added only in Windows 7 and newer versions. Also please note that if someone has recently installed Windows 7 SP1 from scratch, then at the first updates it becomes very bad, while the auto update service is eating the processor, and it can eat several GB of memory. The problem really applies to all versions, just on Windows 7 and older is less noticeable. ”