Why is CPU usage so high on idle?

[UmarG]

Hi!

I noticed that over the last few days my CPU usage has been really high on idle. This picture shows what it was without using my PC for 10 minutes:

I've noticed that the CPU usage spikes to 90 - 100% when doing just about anything (launching Chrome, opening a tab, opening file explorer etc.). This has only been over the last few days, previously my idle CPU would be around 0 - 10%.

What has changed between then and now is that I updated to the Fall Creators update about 2 weeks ago. I also installed Android Studio (and React Native) and set them up last week. Finally, I upgraded my RAM last night (used to have 6GB, upgraded to 12GB - swapped out a 2GB stick for an 8GB stick).

Any idea what could have happened?


Just to note my PC's specs:
CPU: Intel Core i3 4010U @ 1.7GHz
RAM: 12GB (by combining 4GB and 8GB)
OS: Windows 10 (Fall Creators Update, Build 16299)
Graphics: Integrated (Intel HD 4400)

Here's the CPU-Z stats for my CPU:

 

[dudio]

First thing I would do is run MalwareBytes (free) and rule out malware.
Secondly, what do you see if you open up the item that is getting the most use?
Click on the little arrow to the left of it to expand the thread and see what it is.

 

[UmarG]

First thing I would do is run MalwareBytes (free) and rule out malware.
Secondly, what do you see if you open up the item that is getting the most use?
Click on the little arrow to the left of it to expand the thread and see what it is.

I'll try the malware scan. Would Kaspersky suffice? Or do I have to download MalwareBytes?

I just checked again and opened up the first 3 items that were taking up the most CPU resources. That's in the image below. Seems to be mostly system processes. Not sure why they're using the CPU so much.

 

[jr9]

If you have services using the service local host process and taking up lot of resources, sometimes disabling services in services.msc can help. High service host usage is a common problem in Windows 10 especially on less powerful processors. I would start by disabling internet connection sharing if you aren't using it.

 

[UmarG]

If you have services using the service local host process and taking up lot of resources, sometimes disabling services in services.msc can help. High service host usage is a common problem in Windows 10 especially on less powerful processors. I would start by disabling internet connection sharing if you aren't using it.

But why would it start using so much of my CPU now? I've had Windows 10 for almost 2 years now - could it be because of the recent update? In which case, could it be fixed in a future update?

Also, all the conventional wisdom I've read around the internet says to avoid messing with system processes, if you don't know what you're doing (which I don't, in this case).

How safe is it to disable some of the services that are being used? And how can I find out what they do (so that I can figure out if I'm using it or not)?

 

[UmarG]

Well, I tried running a full system scan with Kaspersky and it found no threats. So, I guess I can rule out malware at least.

I'll Google around on the services taking up cpu resources and see what I can disable.

 

[jr9]

Windows Update is known for causing problems. It's really the only core thing on your system that changes modifies it unless you change the hardware. It could be fixed by a future update but I wouldn't hold my breath.

The internet saying not to mess with system processes is correct because Windows needs them. Services are different from system processes though. Services can be disabled and often are. If I don't need "offline files" for example, I can disable that service and only that service stops. Your problem is that "Internet connection sharing" and a couple other services that are related to Windows firewall are using the svchost system process heavily and taking up resources.

I would start by disabling the internet connection sharing service if you don't need it. It's a service that allows your PC to share its internet connection with others. Base filtering Engine and Firewall should be left alone though. If those 2 are still causing issues one workaround is to install a 3rd party Firewall like Comodo or Norton and disable Windows Firewalll and not use it at all.

 

[UmarG]

Windows Update is known for causing problems. It's really the only core thing on your system that changes modifies it unless you change the hardware. It could be fixed by a future update but I wouldn't hold my breath.

The internet saying not to mess with system processes is correct because Windows needs them. Services are different from system processes though. Services can be disabled and often are. If I don't need "offline files" for example, I can disable that service and only that service stops. Your problem is that "Internet connection sharing" and a couple other services that are related to Windows firewall are using the svchost system process heavily and taking up resources.

I would start by disabling the internet connection sharing service if you don't need it. It's a service that allows your PC to share its internet connection with others. Base filtering Engine and Firewall should be left alone though. If those 2 are still causing issues one workaround is to install a 3rd party Firewall like Comodo or Norton and disable Windows Firewalll and not use it at all.

Thanks a lot for the solutions jr9! I started googling around for the services you mentioned and found the solution through another toms hardware thread!

Turns out it's an issue with the Fall Creators update and the Windows Firewall. The solution is to disable the firewall for all network types and then click the button that says "Restore Settings". That fixed everything! My CPU usage is back down to 0-10% now

Full details on the fix can be found here: https://answers.microsoft.com/en-us/windows/forum/windows_10-performance/fall-creators-update-resulting-in-high-cpu-use-by/4711efd5-e068-4d58-bf1c-0abf719c589d?auth=1

Just in case that doesn't work (for anyone else that comes across this thread), there's one other solution suggested here: http://www.tomshardware.com/forum/id-2965897/high-cpu-usage-service-host-local-service.html