Windows 10: Up to 10% CPU usage by process called "System"

I encountered the problem of CPU load up to 10%. Using Progress Explorer, I found that the starting address ntoskrnl.exe!KeReleaseSemaphore+0x8a0 causes such a load. I have attached a screenshot. I tried to update all possible drivers, but it didn't help. I performed a clean boot, but the load remained anyway. Also, I checked in the antivirus through Full Scan and used Driver Verifier, but nothing unusual happened either. What should I do in this case?

:)

 

system process high cpu usage

Hello,

To fix high CPU usage issue, please refer these steps:

Try to identify the process creating this issue.

Download Process Explorer from Microsoft:

Process Explorer - Sysinternals

Run the tool then select the system process, right-click and select Properties.

Switch to the Threads tab. This will show which file is using the excessive CPU usage, from which you can then attempt to diagnose it.

Also refer: [FIX] Windows 10 High CPU Usage Problem

Let us know if this helps!

Note: Included link in this reply refers to blog post by a trusted Microsoft MVP.

 

'System' process high CPU usage

Hi,

you can record a trace using Windows Performance Recorder so that we can take a look at the call stacks to see what the system process is doing;

1. Open a command line as an Administrator;
2. Type the following command in the command line Windows: cd %programfiles(x86)%\Windows Kits\10\Windows Performance Toolkit
3. When you notice a high CPU usage, type this command "wpr -start generalprofile -start CPU"; this will start trace recording.
4. Let WPR record a trace for about 1 minute.
5. Then type this command to stop trace recording "wpr -stop %userprofile%\desktop\MyTrace.etl". The trace file will be created on your desktop.
6. Compress the resulting file (Important)
7. Share it through Send Large Files - Free Secure File Transfer - TransferNow or any other file sharing platform.

If Windows Performance Toolkit is not present on your system, you can download it from this link. After installing it, go back to step 1.

 

"System" process with high CPU usage

I have exactly the same issue (high CPU usage) on a brand new HP ProBook 440 G5 (i7-8550U, pre-installed Win 10 Pro).

I am pretty sure that there is a problem with audio drivers when the computer wakes up from a sleep mode. I first observed that process flow.exe (audio bloatware provided by HP/Conexant) was consuming (after waking up) ~10–15 % CPU. Here's what I did:

• I have updated Windows to 1709, build 16229.251 and installed all updates --> Nothing has changed.
  
• I have updated BIOS to the latest version provided by HP. --> Nothing has changed.
• I have run Windows troubleshooting and HP Support Assistant checks --> No problems found, nothing has changed
• I have manually updated Conexant ISST Audio Drivers (via Device Manager -> Update drivers). Windows installed a newer version. -->
  CPU usage by flow.exe has disappeared, but process called System in thread ACPI.sys+0x21cb0 started consuming ~20 % CPU.
• I have uninstalled all Conexant software&drivers and manually installed generic High Definition Audio Device drivers provided by Microsoft (Driver Date: 21.02.2018). --> ACPI.sys+0x21cb0 still consumes ~20 % CPU.

Same issues are discussed in these threads on HP site:

• ProBook 450 with high CPU usage - HP Support Community - 6520063
  
• HP Probook 440 G5 Fan issue - HP Support Community - 6567212

The result is I cannot use sleep mode (as advised by this post:
https://h30434.www3.hp.com/t5/Business-Notebooks/ProBook-450-with-high-CPU-usage/m-p/6611446/highlight/true#M149605).