Microsoft recently released the preview build of the next Windows cumulative update. Installing the update could potentially improve computer speeds by fixing CPU spikes. If you’ve noticed CPU spikes, it’s worth trying the update to see if it works.
The problem appears to be caused by an undocumented bug with Windows 10. While the Microsoft Feedback Hub is filled with people complaining about the issue, there have been few, if any, responses. Microsoft suggests the issue could be related to a “race condition.” As Microsoft explains it:
“A race condition occurs when two threads access a shared variable at the same time. The first thread reads the variable, and the second thread reads the same value from the variable. Then the first thread and second thread perform their operations on the value, and they race to see which thread can write the value last to the shared variable. The value of the thread that writes its value last is preserved, because the thread is writing over the value that the previous thread wrote,”
The complaints have slowed down since the new preview update KB5001391 was released. The update is classified as a “cumulative update preview for Windows 10 version 20H2,” meaning it has some files from the upcoming Patch Tuesday update scheduled for May 11. Microsoft releases cumulative updates on the second Tuesday of each month.
The support page for KB5001391 does mention a race condition fix related to the update, but only for Windows 10 version 2004. The page also mentions an “issue that causes Isaas.exe memory usage to grow until the system becomes unstable,” among other bug fixes.
There’s no guarantee that installing the update will fix your computer, but it’s worth checking anyway.