Service Host: Local System is a collection of essential system services, including the Windows Update service. Any of the services in this group malfunctioning could be leading to the Service Host Local System High CPU Usage issue.
The most common culprit is the Windows Update service itself. If your PC is facing someissue with the update, it could be stuck in a loop of crashing and retrying as many users have reported.
Of course, this is just one example. The underlying issue causing the high CPU usage could be different in your case. As such, we’ve detailed how you may identify the cause and get the CPU usage back to normal in this article.
What causes Service Host Local System High CPU Usage
As stated, most users face this issue because the Windows Update service isn’t working properly. Other usual reasons for the high CPU usage include:
How to Fix Service Host Local System High CPU Usage
The best way to fix this issue is to identify the exact service that’s causing thehigh CPU usageand troubleshoot the underlying issue. We’ve detailed how you may do so in the sections below.
Identify and Troubleshoot Problematic Service
From the Processes tab in the Task Manager, you should be able to identify the exact service causing the high CPU usage. Additionally, you may also view the resource usage for specific programs via the App History tab in theTask Manager. Here are the steps to do so:
Disable SysMain/Superfetch
As stated, the main reason for Service Host Local High CPU Usage is that some service grouped under it is malfunctioning. In the majority of the cases, users have found this service to beSysMain or Superfetch. We have a detailed article on disabling Superfetch and whether it’s worth it, but for now, here’s an easy way to do it via the Services utility:
Turn Off Delivery Optimization
Delivery Optimization is a feature that enables updates to be downloaded from various sources (other PCs on your network, for instance) rather than a traditional internet server toreduce bandwidth consumption. A lot of users were able to resolve the high CPU usage by disabling this feature, so we recommend that you do the same with the following steps:
Resolve Windows Update Issues
Failed Windows Updates are a major reason for the high CPU usage issue. As such, resolving the underlying issue is very likely to be helpful. Here are the steps to do so:
