Windows 10: Cortana/SearchUI.exe CPU load & not always suspending, build 10586

One of my PCs has developed a new problem with the November update. When I open the start menu, Cortana's CPU usage spikes to 50% and higher (total CPU load hits 100%) which causes a noticeable lag when scrolling in the all programs menu. When the start menu is closed the process' usage usually drops and then it suspends, but for some reason this doesn't always happen and it can remain there for several minutes hammering the CPU.

I have Cortana disabled on this particular machine, inc. history. This problem wasn't there before the current update. I'm also not asking for ways to disable SearchUI, I see there are already many threads about that here.

Any ideas about what could be the cause?

:)

 

I cannot find Apps or Programs by using the taskbar search.

After I restarted Cortana, I still couldn't search for apps using the taskbar search.

I decided to go to the details on Cortana using the Task Manager and noticed that "SearchUI.exe" was suspended.

Could this be the cause of the problem?

Is there anyway to get "SearchUI.exe" to run again?

 

High Disk Utilization 100%

Problem: Upgraded from 8.1 to 10. after few month noticed high disk utilization (every few seconds disk running at 100%). ShellExperienceHost.exe was causing high cpu and memory usage. Found a temporary solution by running following command

in admin mode: net stop superfetch

this command suspends ShellExperiencehost.exe and SearchUI.exe (Cortana?).

I don't really use Cortana on my laptop and wondering how I can permanently disable these 2 processes as they come out from suspend to active mode after awhile.

Are any downsides to disabling these processes completely?

Thank you!