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The System process is using ~16-17% of the CPU:
Originally Process Explorer reported the offending thread to be KeReinitializeAffinityEx:
Today, a Communigy reported they had the same issue which was resolved by installing "2024-03 Cumulative Update Preview for Windows 11 Version 23H2" which I just did. The problem remains but the offending thread is now KeQueryMaximumGroupCount:
The Microsoft Community Support Specialist/Moderator who responded in the Forum redirected me here.
Does anyone have an insight into what is going on, or what diagnostics I should try next?
Thanks. Richard.
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I have exactly the same issue as you: first high system cpu usage because of KeReinitializeAffinityEx, then after installing the update, high cpu usage because of KeQueryMaximumGroupCount.
Would be good to have a quick solution for this.
Hello All,
My suggestion would be to use Windows Performance Recorder (WPR) and Windows Performance Analyser (WPA) to examine the behaviour.
Sharing the data recorded by WPR here might be of value.
The command to gather data for a first quick analysis that I would choose is:
wpr -start CPU -filemode & ping localhost & wpr -stop why.etl -skipPdbGen
The "ping localhost" is just used to delay for 3 seconds; if the high CPU usage is constant then a 3 second sample should be a reasonable sample.Gary
I also tried to analyse the results with the Windows Performance analyser, but I was not able to get any useful information out of it.
Here are the results:
Biggest part seems in nvlddmkm.sys, but when I open it, I get hundreds of empty lines:
<deleted>
Hello Tom,
I posted a reply in the 5 minutes between your last two posts (not yet visible for me to edit/remove). Now that I have seen the second post, it looks like this approach (WPR/WPA) won't be much use; it is well suited to analysing Microsoft software, where symbolic information and good instrumentation is available, but much less useful when investigating problems with Nvidia software.
Gary
@Gary Nebbett : You still helped me: I uninstalled the NVidia driver and did a clean install of the latest driver version and now the problem is fixed!
@Richard Sniderman : Maybe you can also post your results with WPA, so we can look if it is the same cause?
Thank you, thank you thank you!!
I too installed the latest NVidia driver, rebooted and could tell by the "quiet" CPU that the problem was indeed solved - confirmed by both Task Manager & Process Explorer. You are heroes (to me). I spent the latter part of my career running a Software Support Team with Genesys, and am particularly appreciative of this community-based assistance. (It sure made my job a bit easier supporting the products I was responsible for).
Regards. Richard.
Based on analysis suggested by @Gary Nesbit , @Tom Levels who had the same issue, determined that the root cause appeared to be associated with the NVidia driver. He upgraded the driver to the most current and the issue was resolved. Based on the feedback, I did the same, and the issue was resolved for myself as well. I consider the issue closed.