"ntoskrnl.exe!RtlSidHashLookup+0x1ffc" using constantly 1/8 full cpu-core while idle

Hi Gschrempf,

Thank you for the detailed issue description.

It seems that some event is triggering after every 5 minutes. I have come across similar issue where updating the device drivers and running DISM tool helped.

Please visit the following link and install the latest drivers.

http://h10025.www1.hp.com/ewfrf/wc/softwareCategory?cc=us&lc=en&product=5444279

Also install all the Windows updates available (Including the optional updates).

If the issue still persists, use the inbox Deployment Image Servicing and Management (DISM) tool and check if it helps.

a. Open an elevated command prompt. To do this, on the start screen type cmd, right-click Command Prompt, and then click Run as administrator. If you are prompted for an administrator password or for a confirmation, type the password, or click Allow.

b. Type the following commands. Press Enter after each command.

DISM.exe /Online /Cleanup-image /Scanhealth

DISM.exe /Online /Cleanup-image /Restorehealth

c. Close the command prompt then check if it fixes the issue.

Hope the information provided is helpful. Do reply, if you need further help.

hi Babu, thanks for your fast answer!

i have all windows updates installed (with all optional updates).

i also executed the DISM tools with both commands, everything was fine.

i also installed and reinstalled all updates from HP, was quite much work but it didn't helped.

but in the meanwhile i found the windows-service which is generating this high CPU usage after 5 minutes of idle in the "task scheduler": go to "Microsoft -> Windows -> MemoryDiagnostic"

There is the "RunFulMemoryDiagnostic" Service. When executing it directly with right click -> execute, then i get the same CPU-Usage in the Task Manager from "System" with 0,1MBytes of Memory using, but 20% CPU-Runtime (1/8 cores).

i left it running for 20 minutes, then the process finished (i think so), but on the next day the process wants to execute again. So its quite annoying.

I temporarily disabled this service in the task scheduler, since 4 days i dont have this problem any more. So i would think that this is the main cause of the idle problem.

If the process cannot run to the end, it starts again after every 5 minutes of idle, the whole day long and gets interrupted when the user moves the mouse (return from idle).

Maybe its possible for the Microsoft engineers to find a solution for notebooks. Its quite annoying when leaving the notebook for some minutes.

Hi,

Thank you for the reply and sorry for the delay in response.

Let’s run the Memory Diagnostics Tool and check if it finds any issues.

Press Windows key+ X, click and then click Control Panel. In the search box, type Memory, and then click Diagnose your computer's memory problems.‌ If you're prompted for an administrator password or confirmation, type the password or provide confirmation.

Keep us posted on the status of the issue.

here are two files.

the first one:

the second one:

is no software running in background.

here the link:

https://www.dropbox.com/sh/a781uy5oua6j1mi/AACPUuDxYJxc5nAwzk1Fr8gza

with the "RunFullMemoryDiagnostic" deactivated since 2 weeks, i dont have this cpu-usage-problem any more.

in the WPT there was no profile for "first level triage" in the list, the other options are activated.

Hi,

I am sorry for the delay in response.

I understand that disabling “RunFulMemoryDiagnostic” reduced the CPU usage. This issue seems to be caused by faulty memory and that is triggering the Memory test automatically.  

Swap out your RAM modules. Have one RAM connected to the computer and check the CPU usage. This test will help us to find out the faulty RAM.

Hope this helps.

Hi Babu!

I swapped out each of the 2 RAM-modules and ran the "RunFullMemoryDiagnostics" in the "Task Scheduler" (see Screenshots). The Problem stays the same: it runs 10 minutes for each RAM module, then the "System" process is finished and CPU usage goes down to normal 0%.

This problem exists since i bought the HP Envy 17j-011sg notebook in November 2013, i think its very unlikely that both RAM modules are fauly since this date (4GB Samsung RAM + 8 GB ADATA RAM, DDR3L 1066).

If both RAM modules are plugged in, the "RunFullMemoryDiagnostics" runs 20-30 Minutes and then finishes, so the runtime correspondes to the amount of memory (12GB total).

Have you ran this Memory Diagnostic on your own computer / notebook? i would suggest that you find the same problem that this task is running a long time?

here i send you new screenshots from the task manager of Windows 8.1:

https://www.dropbox.com/sh/s4rpdk9u8ycw9ty/AADnZNNdvvjFmTmHu2SZwTrna?dl=0

in my opinion, it would be very helpful if microsoft can reduce the CPU usage of this task, or maybe find a bug in the software why it is running so long?

kind regards,

Gerald (from Austria)

Hi Gerald,

I have exactly the same problem with my new Fujitsu T904. When plugged-in and in idle the CPU usage goes to 30%. As soon as I start working CPU usage goes to 2%. I see that "RunFullMemoryDiagnostics" has comment “The operator or administrator has refused the request” with the time when PC goes from the idle mode. If I run the service manually it will run until end with a message “The operation completed successfully”. But next day it will kick in again.

Kind regards,

Nenad 

here are two files.

the first one:

this is the record with running the memory diagnostic from "task scheduler -> Microsoft/Windows/MemoryDiagnostic/RunFullMemoryDiagnostic". (CPU Usage = 20%, so 1/8 full core).

the second one:

is no software running in background.

here the link:

https://www.dropbox.com/sh/a781uy5oua6j1mi/AACPUuDxYJxc5nAwzk1Fr8gza

with the "RunFullMemoryDiagnostic" deactivated since 2 weeks, i dont have this cpu-usage-problem any more.

in the WPT there was no profile for "first level triage" in the list, the other options are activated.

I have the similar problem with my HP DV6 powered by a Core i5 480M and 4gb ram, running Windows 8.1. 

When my computer goes into idle mode usually after 3 minutes (I have set the screen to switch off after 3 mts) the process ntoskrnl.exe (NT Kernel & System) uses the cpu in excess of 20% casing the laptop to heat up, Fan rpm up etc.. 

I deliberately kept the task manager running many times and every time the cpu usage goes up, ntoskrnl.exe process is the culprit. 

This an annoying problem. I'll try to follow the process suggested by gschrempf above next time this happens.  

this method was suggested in some other forum to mostly detect hardware driver issues with windows 8.

I'm experiencing the same problem. The RunFullMemoryDiagnostic task is triggered by the ProcessMemoryDiagnosticEvents, which itself has multiple triggers. One of them is:

Log: Application, Source Application Error, Event ID: 1000

What this means is every time an application crashes (also for reasons unrelated to faulty RAM) the RunFullMemoryDiagnostic will be scheduled to run during the next On Idle event.

What makes the situation worse in my case is that with plenty of RAM (64GB) the memory diagnostics seem to take a long time to complete. If the task doesn't complete before the user logs on again (idle state is interrupted) the task will restart again on the next idle event. In the worst case the task will never finish.

In my opinion the "application crash trigger" does not make much sense as most application crashes are not related to or caused by faulty RAM.

I strongly recommend that Microsoft considers removing this particular trigger from the ProcessMemoryDiagnosticEvents task.