How to Fix High Disk Use in Windows 11/10 by SysMain Service Host

Windows 10 and Windows 11 both are great operating systems. If you notice a slow performance on a regular basis, this could be due to SysMain (previously known as Superfetch).

We will explain SysMain in this article and help you identify why this service might be causing high disk use.

What is SysMain (Superfetch?)?

Superfetch, SysMain (named after Windows 10’s 1809 upgrade) was added to Windows Vista. It is a successor for Prefetch (an identical feature in Windows XP). To improve the system’s performance, this feature is utilized by OS.

It does this because it is more efficient over time. It first analyzes your RAM usage. Next, the feature will identify which programs are most frequently used on your computer. Superfetch will preload these programs to your RAM once it has all this data. These programs will load faster when you start them.

Superfetch therefore needs resources. Superfetch might be working behind the scenes if you examine the Task Manager’s list of system processes as “Service Host SysMain”:

Superfetch does not deprive any other programs of RAM. Only unused RAM is used by Superfetch. Superfetch will have preference over any newly launched programs regarding RAM space. Superfetch can be used if necessary Free RAM You can also download another app.

You can disable Superfetch if it is slowing down your computer. We will discuss below a few methods to disable Superfetch or fix Service Host SysMain Problem with high CPU use.

SysMain services can be disabled

SysMain runs as a Windows Service, so the easiest way to deactivate SysMain from the Services Console is:

1. Press Win + + R, services.msc, Enter To launch the Services console.
2. For a specific service, scroll through the list from the Services console SysMain.

3. To access service properties, double-click SysMain. Alternativly, right-click on the SysMain service to open properties Properties.
4. Select the Stop To stop the service, click on this button Next, you can expand the Startup Type Select from drop-down menu Disabled.
5. Select OK To save and to exit.

Use the Command Prompt to Disable SysMain

It is faster to use the Command Prompt for SysMain disabling. Here’s how to disable SysMain if you are comfortable with command:

1. Press Win + + R, cmd, Ctrl + + Shift + + Enter To launch an elevated Command Promp.
2. The following command can be copied and pasted into the Command Prompt Window. Click the OK button Enter: :

sc stop “SysMain” & sc config “SysMain” start=disabled

Disable SysMain and the Registry

You can change the registry settings to disallow SysMain if the above methods fail:

1. Press Win + + R, regedit, Enter To launch Registry Editor.
2. You can navigate to this path by using the sidebar on the left or you could copy the text below and paste it into the navigation bar in the top Enter: :

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SysMain

3. Look for the value you are looking for Start Click in the left pane, and then double-click.
4. Change Value Data Select up to 4 OK To save and to exit.

Run SFC Scan

The SysMain High Disk Usage issue can be resolved by using the System File Checker, (SFC.

SFC (System File Checker) is an integrated utility in Windows. It checks the integrity of system files. SFC automatically repairs corrupted system files that it detects during a scan. If system file corruption is the problem, SFC may be able to fix it.

1. Press Win + + R, cmd, Ctrl + Shift + Enter.
2. The following command can be copied and pasted into the Command Prompt Enter: :

sfc /scannow

It will check your hard drive and find corrupt files, then replace them. Start your computer again after the scan has finished. If the Service Host SysMain high-disk usage problem continues, you can check it by restarting the PC.

Update Windows

Always check Windows Update to see if there are any updates available. Microsoft releases patches to address any issues in Windows.

Updates might prove to be helpful if you don’t like the results of previous solutions:

1. Press Win + + I Start the Settings app, and then select Windows Update You can access the right sidebar.
2. Select the Check for updates button.
3. You can select the updated version if they are available Download & install To install them, click the “Install” butto.

Start your computer again and check if the problem is solved.

SSD Replaces the Hard Drive

Replace your older mechanical HDD with one that is more powerful and reliable if you have been using it for quite some time Solid State Drive The SSD (Supportive Storage Device) is a way to optimize your computer’s performance as well as solve high disk usage issues.

If you have exhausted every option to resolve the problem, this might be a good idea.

Modern computers all have slots that can accommodate SSDs. If you haven’t purchased SSDs before, please refer to our SSD purchasing guide To make informed decision.

SysMain Disk Usage. Normalized

You should be able to resolve SysMain disk use with one of the following fixes. SysMain does not necessarily consume too much RAM. Windows created this feature intelligently to optimize RAM usage and You will experience faster performance with the most commonly used app.

If it uses a large amount of memory, you can disable it permanently without any severe consequences. You can also fix system files corruption and install Windows updates to resolve the problem without having to disable SysMain.