Windows 10: ACPI.sys high CPU on system power-on but not restart fast boot/startup disabled

I'm puzzled by the following issue:


When I power-on my clean-installed Windows 10 Pro 2004 I notice high load on one CPU core:





Processes shows me "System Interrupts", under closer examination I see ACPI.sys to be responsible:





Which typically points to a HW and/or driver related issue. So I check and update all device drivers to the latest available version. Problem seemed to be solved at first, as I restarted after driver installation, getting an expected CPU load as below:




To my surprise, the issue is always back after I shutdown the system and do fresh power-on: ACPI.sys keeps one core occupied edit: fast startup is deactivated, so the system doesn't hibernate, but powers-down completely and does a clean boot


When I just restart the system NB: fast boot in EUFI BIOS is deactivated, so it is always a full restart, everything seems back to normal.


System logs are inconclusive.


Any idea where to search?


Yes, ACPI.sys is verified as original. Latest BIOS installed as well. All HW is functional

:)

 

ACPI.sys high CPU on system power-on but not restart (fast boot/startup disabled)

I'm puzzled by the following issue:

When I power-on my clean-installed Windows 10 Pro 2004 I notice high load on one CPU core:





Processes shows me "System Interrupts", under closer examination I see ACPI.sys to be responsible:





Which typically points to a HW and/or driver related issue. So I check and update all device drivers to the latest available version. Problem seemed to be solved at first, as I restarted after driver installation, getting an expected CPU load as below:





To my surprise, the issue is always back after I shutdown the system and do fresh power-on: ACPI.sys keeps one core occupied (edit: fast startup is deactivated, so the system doesn't hibernate, but powers-down completely and does a clean boot)

When I just restart the system (NB: fast boot in EUFI BIOS is deactivated, so it is always a full restart), everything seems back to normal.

System logs are inconclusive.

Any idea where to search?

(Yes, ACPI.sys is verified as original. Latest BIOS installed as well. All HW is functional)

 

Windows 10 System High CPU Usage ACPI.sys

Ok, was killing me... Found this solution:

1. Using Windows Performance Recorder and Windows Performance Analyser from the Windows SDK kit, did a 30 second CPU trace and identified the ACPI.sys driver as the final call in the "System and Compressed Memory" task stack trace that was killing my CPU
usage and keeping the laptop fan going hard.

2. Remembered that I'd recently changed BIOS to use ACPI for new SSD in laptop.

3. Note that ACPI.sys also handles many hardware related Power Management and motherboard interrupts ...

4. Bit of googling for ACPI.sys and CPU usage, settled on Intel Gigabit Ethernet driver set for Wake on LAN. Disabled WOL in driver "Power Management" settings and my problem disappeared.

Prior to this I'd been tearing my hair out trying to find a relationship to the "compressed memory" portion of this task and recent Windows updates... turned out to be not relevant.

 

'System' process high CPU usage "ACPI.sys!GetNameSpaceObjectNolock"

hi

I have a hp ProBook 650 G2 with

Microprocessor: Intel(R) Core(TM) i7-6600U CPU @ 2.60GHz

system board: 80FD KBC Version 22.73

System BIOS: N76 Ver. 01.42

system Memory: 16GB

windows specifications

Edition: Windows 10 Enterprise

Version: 1903

Installed on 03/09/2019

OS build 18362.356



However, the CPU is always running between 18 to 25 % on the System process even when the laptop is idle.

Using windows performance analyser from 18362.1.190318-1202.19h1_release_WindowsSDK.iso

I can see it's the ACPI.sys which is consuming the CPU,

After loading the symbols in WPA after capturing computation

I can see its ACPI.sys!GetNameSpaceObjectNolock with

ntoshrnl.exe! strchr and ACPI.sys!memcpy that is consuming the CPU.

What I can not work out is how to stop or slow this process down.



Can someone please point me in the correct direction,

It’s not helpful to have a lovely laptop and wasting 25 % CPU on this for no reason I can see.

I can provide the WPA files if it would be of use.





Things I have tried to identify the problem, but none of this stopped this high CPU usage.

a Clean Boot

running in save mode

disk optimisation

disk clenup

some I can not even remember.